The Pakistan State Oil (PSO) caught participants on Karachi Stock Exchange (KSE) by surprise on Friday as the premier Pakistani bourse ended the week with handsome gains of more than 300 points amid improved turnover. The benchmark KSE 100-Index jumped 1.19 percent, of 304.35 points, to 25,783.28 points Friday, as against 25,478.93 points reported Thursday. During the week that ended on Feb. 28, the key index gained 179. 93 points despite three out of five trading sessions ending in red zone. The KSE All Share Index surged 0.85 percent or 162.01 points to 19,282.40 points, the KSE 30-Index augmented 0.98 percent or 182. 08 points to 18,755.18 points, whereas the KMI 30-Index advanced 1. 36 percent or 575.17 points to 42,886.67 points. During Friday's trading session, the key index hit an intraday high of 25,880.55 points, as against an intraday low of 25,477.36 points. PSO's surprised earnings and payout caused across the board rally on the local bourse where foreign capital inflows also helped boost the sentiment. PSO, Maple Leaf Cement and BankIslami Pakistan Limited closed at their upper limits while oil stocks and cement companies also rallied. Trading volume swelled by 69.795 million shares to 234.88 million shares, turnover added by 5.52 billion rupees (52.53 million dollars) to 9.84 billion rupees (93.70 million dollars), whilst market capitalization increased by 47.33 billion rupees ( 450.79 million U.S. dollars) to 6.28 trillion rupees (59.80 billion dollars). During the week under review, the Karachi bourse recorded a total trading volume of 1.09 billion shares, with daily volume averaging 217.21 million shares. Among the 369 active scrips Friday, prices of 185 issues declined, 172 advanced, whereas values of 12 other companies stayed unchanged. Jahangir Siddiqui Company Limited, TRG Pakistan Limited and Bank of Punjab Rights were most heavily traded, with volume at 18. 61 million shares, 17.68 million shares and 15.74 million shares, respectively. Pakistan Tobacco was the star performer as it rose 38.14 rupees (36.32 U.S. cents) to close at 801.07 rupees (7.62 dollars), while Nestle Pakistan led the major losers by falling 338 rupees (3.21 dollars) to finish at 9,287 rupees (88.44 dollars).