Tuesday, February 25, 2014

Basel 111 Attributes Calculation



·       EAD ( Exposure at Default)-
Estimated future additional draws of principal and accrued but unpaid interest and fees that are likely to occur over a one- year horizon assuming the wholesale exposure or the retail exposures in the segment were to go into default.
          EAD=max {0, [(Exposure—Collateral) +PFE]},
For Stress - PFE (Potential Future Exposure)-
99th %ile, one-tailed confidence interval for an increase in the value  of(Exposure—Collateral) over a five-business-day holding period for repo-style transactions or over a ten- business-day holding period for eligible margin loans using a minimum one-year historical observation.
For the off-balance sheet component of a wholesale exposure or segment of retail exposures EAD means the notional amount of the exposure or segment.
Margin Loans – Credit collateralized by liquid assets. Ex. readily available marketable debt.










·    LGD=
An,  account of historical losses that a firm suffers due to counterparty defaults, frauds, damages, etc. 50 % for unsecured transaction and 70 % for subordinate debt.
A.    When Collateral is there and there is chance of double default or counterparty credit risk-
LGD = LGD * E▪/E
Where E▪ = max (0, [EAD*(1+ He) – C * (1-Hc – Hfx)]
He = Haircut Appropriate for exposure.
Hc = Haircut Appropriate for Collateral.
Hfx = Haircut Appropriate for Foreign exchange.
Haircut is defined as %age by which asset value, margin, collateral or currency market value is devalued.
B.    LGD =
Economic Loss / Exposure at Default
= [Exposure at Default – PV*(Recoveries or collateral) + PV*(Costs)] / Exposure at Default.
PV is a function of Discount rate = Estimating discount rates as
o   Weighted average cost of capital- WACC = Wd*(Kd)*(1-t) + Wpfd*(Kpfd) + (We)*(Ke).
Kpfd = Dividend / Share Price.
o   Opportunity cost of funds.
C.     LGD =
-         1- Recovery Rate.
Recovery Rate –
1.     By Beta Distribution-
Alpha- tells us center,
And Beta tells us shape
Alpha = {(LGD Mean) ^2 * (1 - LGD Mean) / Variance LGD)} – Mean LGD.
Beta- Tells us shape-
 = Alpha * [(1/Mean LGD) – 1]
Recovery Rate = alpha / (Alpha + Beta).
LGD averages and standard deviations are estimated by a historical analysis of recovery history.


2.     Value Recovery Process Models=
= Recovery value/ PV of Future Cash Flows

3.    Instantaneous Recovery Rate Models

·        For bonds, it is possible to determine market recovery rates, which can be calculated as the ratio of the actual market price and the nominal value

 Identify stress points based on historical default rates and/or macroeconomic indicators, estimate default rates during these stressed conditions and calculate their averages. Plug these default rates into a stressed LGD model.
Compute weighted average LGD across these stress points and compare them with average LGD over the cycle. Use the higher of the two for capital calculation purposes. Scaling factor of 1.06 for BASEL AND 1.25 for CAD (EU) to reflect downturn risk.

The BCBS Basel III minimum requirements impose a downturn LGD floor of 10 per cent for Residential mortgage portfolio and 15% for High Volatile Commercial Real Estate.










·      PD ( Probability of Default)-
Retail Credit: Logistic regression is the de-facto industry standard for, Modeling PD for retail exposures.
Wholesale Credit: Historically, qualitative scorecards have been used to assign ratings to wholesale obligors.

The PD for each wholesale obligor or retail segment may not be less than 3 %.
Method – 1
·         By logistic regression to calculate PD and incorporated macroeconomic variables-
Dependent Variable-
 Taking two Non default companies assigning Dependent variable as zero and by taking two default companies data assigning 1 to them.
Default companies, Among nonbanks-
only one institution initially rated 'AAA' has ever defaulted--
- Ally Financial, formerly known as GMAC Financial, a subsidiary of General Motors Corp. S&P downgraded Ally to 'SD' from 'CC'
Among Banks-
The largest banks to be acquired have been the presumed
 Merrill Lynch acquisition by Bank of America,
the Bear Stearns and Washington Mutual acquisitions by JPMorgan Chase, and
the Countrywide Financial acquisition also by Bank of America.
Independent Variables- Historical Data-
·        Profitability ratios- Operating Profit Margin, Interest Coverage Ratio, Return on Equity.

·        Leverage Ratio- Debt/ Equity, Debt Ratio – (Debt / Total Assets),

·        Activity ratio –  Accounts Receivable Ratio, Payable Ratio.

·        Liquidity Ratio-  Quick Ratio, Operating Cash Flow Ratio (OCF / Total Debt.

·        Coverage Ratio:-  Debt to Service coverage , Interest service coverage ratio.

Ratios with high correlation with default rates and linear relation should be selected.

·        Macroeconomic variables like (GDP growth, Interest Rates, CPI, and HPI etc.) of current economic conditions.
Than after getting Logit for variables mentioned above in different time horizons.

·        Financial ratios that have the highest correlation coefficients (r) with the individual possibility of default were selected.
Used equation = e*L/(1 + e*L) to get PD.
PDs from averages of historical default rates
Assigned ratings (0,.5) - Reliable

(.5, 1)- Non Reliable companies.

-         Then, the rating is subsequently mapped to a master scale to derive PDs.
-          For stress testing historical values were taken as in recessionary or mild recession period).
The highest (Max), the least (Min) values and the median (Me) of financial ratios and the individual possibility of default (p) were found. The intervals of values were divided into two parts: from Min to Me and from Me to Max (Fig. 2). Every of these two parts were divided into 4 equal intervals. The scores (0-7) were attributed to these 8 intervals. The higher scores indicate the stronger financial condition of companies. So the highest scores were attributed to companies which were characterized by low debt ratio (IK1) and low individual possibility of default (p).

Altman Model for Ratings-
= 1.2 * (WC/TA) + 1.4 * (RE/TA) + 3.3 * (EBIT/TA) + 0.6 * (MC/Debt) + Sales/ Total Assets.
Score > 3.1 “Good”
1.8 > Score > 3.1 “Grey Period”.
Score < 1.8 “Bankruptcy”






Analysis of Logistic Regression Output’s-

-         Multiple R - The correlation coefficient between the observed and predicted values. It ranges in value from 0 to 1. A small value indicates that there is little or no linear relationship between the dependent variable and the independent variables.
-         R- Square- Square of Correlation i.e square of multiple R.  It ranges from zero to one, with zero indicating that the proposed model does not improve prediction over the mean model and one indicating perfect prediction.
-         Adjusted R- Square - Adjusted R2 is used to compensate for the addition of variables to the model. Adjusted R-squared will decrease as predictors are added if the increase in model fit does not make up for the loss of degrees of freedom. Likewise, it will increase as predictors are added if the increase in model fit is worthwhile.
-         Significance F – Tells us that output is not by chance. Smaller the value greater the probability that output is not by chance. Significance F tells us the probability about the output is a good fit.
-         P-Value - Smaller the value greater the probability that output is not by chance.
-         F – Regression Mean Square / Residual Mean Square.
-         Sum of Squares due to Regression-  is a quantity used in describe how well a regression model, represents the data being modeled. In particular, the explained sum of squares measures how much variation there is in the modeled values and this is compared to the total sum of squares, which Used for t-test and f-test calculations.
-         Residuals- are the difference between the observed values and those predicted by the regression equation.
-         Residual sum of squares- measures how much variation there is in the observed data, and to the, which measures the variation in the modeling errors. A smaller residual sum of squares is ideal.
-         Mean Square – Sum of Square / Degrees of Freedom.
-         Residual Mean Square - . A smaller residual sum of squares is ideal.




Basel III Supplemental Market Risk Capital Requirements

1.     The Existing Value at Risk based Capital Requirement.

            Maximum of -
·        VaR (99.9% of one tailed confidence interval at 10 days VaR).
·        Average of these metrics over the previous 60 business days.
Maximum value is then multiplied by multiplier m.
VaR Calculated as –
Inputs - Portfolio Value, Volatility in currency (from Historical record), Confidence Interval (99.9 %).
Calculating –
Student t distribution – TINV (1 – CI) ^2, Degree of Freedom = Say is x.
VaR = x * Volatility.
Multiplier “m” depends on exceptions (If the quarterly back testing shows that the bank's daily net trading loss exceeded its corresponding daily VaR-based measure, a back testing exception has occurred) while validating the model-
¨     Green Zone  :          0-4 exceptions
¨     Yellow zone :           5-9 exceptions
¨     Red zone        :          10 or more exceptions

1.     Minimum of 3. Than addition to this should be between (0, 1). Means maximum of 4.
2.     4 or fewer exceptions = 3.
3.     5 exceptions                 = 3.4
4.     6 exceptions                 = 3.5
VaR = max ( Var of Last 10 days, multiplier * Average VaR of Last 60 Days)
2.     A Stressed Long Term Capital Requirement.
Same as VaR of Basel 11 except-
10-day, 99th %ile, one-tailed confidence interval value-at-risk   measure of the current portfolio, with model inputs calibrated to historical data from a continuous 12-month period of significant financial stress relevant to the bank’s portfolio.
The stressed VaR should be calculated at least weekly.

3.     A Long Term Incremental Risk Charge.
The Long‐Term Incremental Risk Charge (LTIRC) for a bank’s portfolio under the IMA requires estimates of future credit losses arising from specific risks (default and migration) over a one‐year capital horizon under the entire range of potential risk factor vector and yield curve sample paths.
·        An one‐year capital horizon at a 99.9% confidence level.
·        In liquidity horizon (  the time to liquidate or hedge a given exposure) be less than the smaller of three months or the contractual maturity of the position is to be that which would prevail in stressed market conditions and cannot
4.     A Comprehensive Risk Capital Requirement.
The Comprehensive Risk Capital Requirement represents an estimate of all price risks of the bank’s portfolio of correlation trading positions over a one‐year time horizon at the 99.9% confidence level, again assuming maintenance of a constant level of risk over the one‐year capital horizon.
 Correlation positions include:
 A securitization position for which all or substantially all of the value of each of the   underlying exposures is based on the credit quality of a single actively traded company, or
 A non‐securitization position that hedges a securitization position described above.
Calculation by detailed analysis of the default adjusted performance of each underlying exposure, with special attention to the degree of co‐variation in such performance.
5.     A Specific Risk Charge.
Specific risk is the risk of losses of market risk exposures caused by factors other than broad market movements, including event risk and idiosyncratic risk (assets with zero or no correlation with market). E.x. News that is specific to either one stock or a group of companies, such as the loss of a patent or a major natural disaster, labor problems, management records to adapt changes.
6.     General market risk or Systematic Risk- is defined as changes in the market value of positions resulting from broad market movements, such as changes in the general level of interest rates, equity prices, foreign exchange rates, or commodity prices.
·        Specific Risk Charge

Maturity
Coupon
Value
A
45 days
12.5%
25
B
9 months
9
-15 (short)

.3% for time band 0- 6 months.
1.125% for 6 – 24 months.
1.8% for 24 or more
 - Based on maturity charge on A = .3% of 25
And on B is = 1.125% of -15.

·        General Risk Charge (Systematic Risk)-
Based on market movements.
Net Open position + vertical Disallowance + Horizontal Disallowance.
Net Open Position –
Is calculated on net open position (Long + Short (Short has –ve value) positions) of the zone. As, for 1 to 3 months and for 3 to 6 months and 9 to 12 months.
Modified duration multiply by exposure (Value) of each position than adding all.
Vertical Allowance – Applicable when positions are offset (smallest of mode of amount in time band) with in time bracket.


Because of Basis Risk. Calculated on offset amount.
Value * Modified Duration * 5%.
Vertical disallowance is applicable under 3-6 month time band and 7.3- 9.3 year time band.

Horizontal Allowance –Netting of long short position across time bands. Est Than smallest of mode of amount across time bands.   When positions are offset in time bracket.  Because of imperfect correlation of prices across different maturities. Yield curve risk.

·        Total risk Charge for bonds – Specific Charge + General risk charge.
·        Total Capital Charge for Equity Position – 11.25% (Specific Risk Charge) of Gross Equity Position + 9% (General Risk Charge) of Gross Equity Position.
·        Total Capital Charge for Foreign Exchange & Gold Portfolio – 9% (Specific Risk Charge) of Net Position + 9% (General Risk Charge) of Net Position.
·        There is No specific risk charge on Derivatives Position. General risk Charge is applied in same manner as for equities, Bonds and Foreign Exchange & gold Portfolios.

Capital Adequacy Directive (Market Risk same as in Basel) is based on the European Union version of Basel. Scaling Factor 1.25 is used in calculation instead of 1.06 as in Basel.

RAROC ( Risk Adjusted Return on Capital)-
An adjustment to the return on an investment that accounts for the element of risk. Risk-adjusted return on capital (RAROC) gives decision makers the ability to compare the returns on several different projects with varying risk levels. Also used for performance evaluation.

Asset Correlation-
Joint Behavior of asset values of borrowers. Decreasing function of PD but increasing function of Asset size.
Calculated as-For Residential, Corporate, Sovereign = 0.12 + 0.12 * e^ (50 * PD).
For HVCRE – 0.12 + 0.18 * e ^(50 * PD).
1.     Estimates of asset correlations were developed through a two-step process.
-          First, economic capital allocations for single-family mortgages were generated using these models of mortgage credit risk calibrated with industry data.
-         Second, an asset-correlation parameter was “reverse engineered” to match as closely as possible the capital charges implied by the Basel II formula with the economic capital allocations derived.
2.     Can be calculated by Regression Analysis-
a)     Put X range and Y range
b)    In the result adjusted R- Square is the correlation.

·    Stress Testing –
Stress testing is fairly developed in the area of market risk.
Same as VaR of Basel 11 except-
10-day, 99.9th %ile, one-tailed confidence interval value-at-risk   measure of the current portfolio, with model inputs calibrated to historical data from a continuous 12-month period of significant financial stress relevant to the bank’s portfolio
Banks do that
Sensitivity Analysis for Stress Testing-
Discovering which risk factors have the biggest impact on the portfolio risk in terms of the VaR or whatever is used for the evaluation of unexpected losses, is the target and the benefit of sensitivity analysis.

Ø Unexpected loss = VaR – Expected Loss (PD*EAD*LGD).
Ø Unexpected Loss = EAD * {PD * σ^2(LGD) + (LGD) ^2* σ^2(PD)} ^.5
o   σ^2(PD) = PD * (1-PD)
           
Usually done by modeling risk parameters as a function of stressed macroeconomic variables (e.g., GDP, interest rate risk, foreign exchange
Risk, equity price risk, and commodity price risk, unemployment rate, Inflation, CPI, HPI etc.) Corresponding  to different downturn conditions (e.g., mild recession,  severe recession, etc.) e.x.
·        Oil crisis 1973/1974
·        Stock market crash (Black Monday 1987, global bond price crash 1994, Asia 1998).
·        Terrorist attacks (New York 9/11 2001, Madrid 2004) or wars (Gulf war 1990/1991, Iraq war 2003)
·        Currency crisis (Asian 1997, European Exchange Rate Mechanism crisis 1992, Mexican Peso crisis 1994).
·        Emerging market crisis
·        Failure of LTCM5 and/or Russian default (1998)
 And compare the capital requirements against their current capital level.
Calculate the unexpected loss as the difference between VaR for a confidence level of 99.99% and expected loss.

Other model, the projected figures for the main macroeconomic variables are used to estimate the future income statement and balance sheet of each company and on this basis to calculate individual probabilities of default
(PDs).  Data are then aggregated to estimate the banking sectors
Total loan loss.

·    Data Validation-
Back-testing procedure consists of calculating the number of times that the operational losses fall outside the VaR estimates, these are called exceptions.
Banks have to validate their models on an ongoing basis.
Model should be validated in every 10 days.
Is used to calculate multiplication factor.
If the quarterly back testing shows that the bank's daily net trading loss exceeded its corresponding daily VaR-based measure, a back testing exception has occurred.

Model for Data Validation-
Hosmer and Lemeshow or Chi- Square.
Five groups were formed. For every group the average estimated default Probability is calculated and used to derive the expected number of defaults per group. Next, this number is compared with the amount of realized defaults in the respective group. Then, test statistic of groups is used for the estimation sample is chi-square distributed in turn calculating p-value for the rating model.
Calculated as =
P-Value – The closer the p-value is to zero, the worse the estimation is.
o k =  (number of rating classes), ni = number of companies in rating class i, Di is the number of defaulted obligors in class i, pi is the forecasted probability of default for rating class i
o Compare with p-value.
o No critical value of p that could be used to determine whether the estimated PD’s are correct or not
o The closer the p-value is to zero the worse the estimation is .
o First –all else equal, the greater the chi square number, the stronger the relationship between the dependent and independent variable.
o Second –the lower the probability associated with a chi-square statistic, the stronger the relationship between the dependent and independent variable.
o Third –If your probability is .05 or less, then you can generalize from a random sample to a population, and claim the two variables are associated in the population.









Numerator covers tier 1, tier 2, tier and
·        The sum of tier 2 and tier 3 capital allocated for market risk may not exceed 250 % of tier 1 capital. As a result tier 1 capital must equal at least 28.6 % of the measure for market risk.
·        The  sum of tier 2 (both allocated and excess) and allocated tier 3 capital may not exceed 100 % of tier 1 capital (both allocated and excess)
·        Term subordinated debt and intermediate-term preferred stock and related surplus included in tier 2 capitals (both allocated and excess) may not exceed 50 % of tier 1 capital (both allocated and excess).
·        Tier 3 capital is subordinated debt that is unsecured, is fully paid up, has an original maturity of at least two years, is not redeemable before maturity.
Ø Capital Adequacy Directive III (CAD III) increased capital requirements for the trading book and complex securitization positions and introduced stressed value-at-risk capital requirements and higher capital requirements for re-securitizations for both in the banking and trading book.
Ø Liquidity coverage ratio- The liquidity coverage ratio (LCR) will require banks to have sufficient high quality liquid assets to withstand a 30-day stressed funding scenario that is specified by supervisors. Will, be introduced in 2015.
(Stock of High Quality Liquid Assets / Net Cash Outflow for 30 days) >=100%.
Ø Net Stable Funding - ratio measures the amount of available longer-term stable sources of funding over the required amount under a one year stress scenario. Will, be introduced in 2018.
(Available Stable Funding / Required Stable Funding) >=100%.

Ø Covered Positions are defined as all on- and off-balance sheet positions in the
Bank’s trading account. Covered positions exclude all positions in the trading account that, in form or substance, act as liquidity facilities that provide liquidity support to asset-backed commercial paper.
Ø  Maturity Mismatch- occurs when the residual maturity of a credit risk mitigant is less than that of the hedged exposure(s). 3 months.
Ø Leverage Ratio   (Tier 1 / Balance sheet and other off Balance Sheet      Exposures) >= 3%
Ø Free Cash Flow- A measure of financial performance calculated as operating cash flow minus capital expenditures.
Macroeconomic variables
·        Interest Rate at a Particular Tenor on a Specified Yield Curve Denominated in a Given Currency
·         Underlying Risk Factor for a Dynamic Yield Curve Model for a Specified Yield Curve in a Given Currency
·         Spot FX Rate Between a Base Currency Denomination and Another Currency Denomination
·         Equity Market Index with a Specified Market Symbol in a Given Currency Denomination
·        Black Scholes Implied Volatility for an Option Contract on an Underlying Asset, Rate Index, or Spot FX Rate.
·        The economic value of securitization tranche instruments (securitized assets and synthetic CDOs) as the expected present value of projected future tranche cash flows by applying Monte Carlo pricing methods. The present value of future tranche cash flows is calculated using discount rates obtained from the pricing yield curve applicable to the securitization
tranche instrument.
·        Interest Rate Spread on a Specified Category of Bonds in a Specified Currency Denomination
·        Interest Rate Spread on Bonds with a Specified Credit Rating
·        Macroeconomic Risk Factors such as GDP Indices, CPI, Purchasing Power parity ,Industrial Production index,  Inflation Rates, or Housing Price Indices
·        Performance Risk Factors for Industries, Asset Classes, or Other Market Segments
·        Credit Risk Factors such as Obligor Default Intensity and Recovery Rate
·        Counterparty‐Specific Risk Factors Representing Idiosyncratic Risk.
Operational Risk –
1.     Basic Indicator Approach-
Average of total income of last 3 years * Alpha (Currently 15%)

Financial Statements Screening
·        For each of the key expense components on the income statement, calculate it as a %age of sales for each year.
·        Look for non-recurring or non-operating items.  These are "unusual" expenses not directly related to ongoing operations.
·        Determine whether the company’s dividend policies are supporting their strategies.
·        Examine the cash flow statement, which gives information about the cash inflows and outflows from operations, financing, and investing.
·        Whether fixed assets grown rapidly in one or two years, due to acquisitions or new facilities?  Has the proportion of debt grown rapidly, to reflect a new financing strategy?  

Forecasting Attributes- Cumulative Accuracy Profile
It plots the empirical cumulative distribution of the defaulting debtors ^ CD against the empirical cumulative distribution of all debtors ^ CT. For a given rating category Ri, the %age of all debtors with a rating of Ri or worse is determined. Next, the %age of defaulted debtors with a rating score worse than or equal to Ri. This determines the point A in Fig. 13.1. Completing this exercise for all rating categories of a rating system determines the CAP curve. Therefore, every CAP curve must start in the point (0, 0) and end in the point (1, 1).

Accuracy Ratio = aR / aP,
aR is the area between the CAP curve of the rating model and CAP curve of the random model.
aP is the area between the CAP curve of the perfect forecaster and the CAP curve of the random model.








Basel 111-   "Basel III is a comprehensive set of reform measures, developed by the Basel Committee on Banking Supervision, to strengthen the regulation, supervision and risk management of the banking sector".
Basel 3 measures aim to:
→  improve the banking sector's ability to absorb shocks arising from financial and economic stress, whatever the source . →  improve risk management and governance . →  strengthen banks' transparency and disclosures.
Pillar 1 : Minimum Regulatory Capital Requirements based on Risk Weighted Assets (RWAs) : Maintaining capital calculated through credit, market and operational risk areas.
Pillar 2 :  Supervisory Review Process : Regulating tools and frameworks for dealing with peripheral risks that banks face.
Pillar 3: Increasing the disclosures that banks must provide to increase the transparency of banks
Major Changes-
 (a) Capital Conservation Buffer:    Banks will be required to hold a capital conservation buffer of 2.5%.  The aim of asking to build conservation buffer is to ensure that banks maintain a cushion of capital that can be used to absorb losses during periods of financial and economic stress.
(b) Countercyclical Buffer:  Basically to increase capital requirements in good times and decrease the same in bad times.  The buffer will slow banking activity when it overheats and will encourage lending when times are tough i.e. in bad times.  The buffer will range from 0% to 2.5%, consisting of common equity or other fully loss-absorbing capital.
 (c) Minimum Common Equity and Tier 1 Capital Requirements :   The minimum requirement for common equity has been raised under Basel III from  2% to 4.5% of total risk-weighted assets.  The overall Tier 1 capital requirement, consisting of not only common equity but also other qualifying financial instruments, will also increase from the current minimum of 4% to 6%.   Although the minimum total capital requirement will remain at the current 8% level, but will increase to 10.5% when combined with the conservation buffer.
 (d) Leverage Ratio A leverage ratio is the relative amount of capital to total assets (not risk-weighted).   This aims to put a cap on swelling of leverage in the banking sector on a global basis.   3% leverage ratio of Tier 1 will be tested before a mandatory leverage ratio is introduced in January 2018.
Comparison of Capital Requirements under Basel II and Basel III :

Requirements
Under Basel II
Under Basel III
Minimum Ratio of Total Capital To RWAs
8%
10.50%
Minimum Ratio of Common Equity to RWAs
2%
4.50% to 7.00%
Tier I capital to RWAs
4%
6.00%
Core Tier I capital to RWAs
2%
5.00%
Capital Conservation Buffers to RWAs
None
2.50%
Leverage Ratio
None
3.00%
Countercyclical Buffer
None
0% to 2.50%
Minimum Liquidity Coverage Ratio
None
TBD (2015)
Minimum Net Stable Funding Ratio
None
TBD (2018)
Systemically important Financial Institutions Charge
None
TBD (2011)


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