The Sensex failed to sustain gains witnessed last week, and slipped 1.9% (125 points) during the week ended April 8 despite positive activity by institutional investors and easing crude oil prices.The Sensex fluctuated in a wide range of 6,649.42 points and 6,456.84 points before ending the week at 6,479.54 points as against the last weekend close of 6,605.04 points - a net fall of 125.50 points.Trading was dull in the last two sessions of the week despite fairly good fund inflows. Foreign institutional investors (FIIs) reported net investments of Rs 502.40 crore in the first four days of the week while domestic funds made net purchases of Rs 120.20 crore during the same period.Market participants were unwilling to take risks in the prevailing situation despite confidence expressed by the government in managing inflationary pressure due to high oil prices. The government also ruled out any immediate hike in petrol and diesel prices as well as hike in interest rates in the medium term.The volume of business was relatively low on the BSE and the NSE at Rs 9,984 crore and Rs 21,271 crore,respectively, when compared with last week's turnover of Rs 10,318 crore and Rs 22,359, respectively.