IF you feel civil servants' salaries are too high, wait till you see how much they get in perks. Their fringe benefits can be worth more than their basic salary. Just take a look at the Staff Cost Ready Reckoner, an annually updated publication produced by the Treasury to help government departments estimate their total staff costs. As the table shows, the value of perks enjoyed by civil servants can range from about half to 11/2 times their basic salary. But before we jump to any conclusion, a caveat is in order. The value of most of the perks is notional and cannot be cashed and pocketed by civil servants. The perks include a pension, contributions to the Widows and Orphans/Surviving Spouses' and Children's Pension Schemes, housing benefits, leave (including maternity leave), leave passages, education allowances and medical and dental benefits. A pension is payable to civil servants only on their retirement and their relatives benefit from the surviving spouses and children's pension scheme only if they die prematurely. The leave passages and education allowances ensure civil servants are paid travelling costs and for the expense of sending their children to school. A major component of their perks is housing benefits, which takes several forms. It can be the notional market rent of a government flat, a private tenancy allowance that covers the rent, or a home mortgage allowance that is partly accountable. In the table, senior civil servants whose perks were worth more than their basic salary in 1994 were likely to be living in spacious government quarters whose equivalent market rents were driven to a wildly inflated levels during last year's property boom. The latest Staff Cost Ready Reckoner is likely to show the value of their perks has now fallen because of the downturn in the market. Measures introduced in the past few years are likely to reduce the notional value of housing benefits enjoyed by civil servants. The introduction of the Home Finance Scheme in October 1990, under which civil servants are given a cash allowance for 10 years to buy their own property, has encouraged many to give up their entitlement to non-departmental quarters and a private tenancy allowance, which have no time limit.