The Nairobi Securities Exchange (NSE) 20 Share Index lost momentum Friday and slid below the 4,000 mark where it had crossed to at the start of the week.

The index closed the day 1.36 percent lower at 3,999.33, dropping from 4,054.44 where it had peaked Thursday due to increased trading.

All the other indices too went down marginally, with the All share Index (NASI) recording a 0.64 percent fall to close at 146.50 while the NSE 25 Share Index lost 14.03 points or 0.33 percent to settle at 4219.04 points.

Equity turnover stood at 4.3 million US dollars, down from 5.9 million dollars the previous day with Equity Bank, Safaricom, KCB and Athi River Mining accounting for 90 percent of Friday's total turnover.

Week on week, turnover rose to 202 million dollars from the previous week's 108 million dollars. The number of shares traded stood at 75 million against 86 million posted the previous week.

During the week, Safaricom remained the biggest mover with 36 million shares changing hands at between 0.16 dollars and 0.17 dollars, which represented 48 percent of the week's traded volume.

The banking Sector moved 22 million shares, which accounted for 30 percent of the week's traded volume. In the category, Equity Group Holdings was the most heavily traded counter with 12 million shares changing hands at between 0.40 dollars and 0.41 dollars.

The energy and petroleum sector came third, moving 4.2 million shares, which accounted for 6 percent of the week's traded volume.

The insurance sector moved 3 million shares, which represented 4 percent of the week's traded volume while the manufacturing and allied sector moved 3.3 million shares.