NAIROBI (Reuters) - Kenya's Nairobi Securities Exchange (NSE), which is listing its shares next month, posted a 29 percent year-on-year fall in its pretax profit for the first half to 158.2 million shillings($1.78 million). The 60-year old bourse, whose initial public offering closed on Aug. 12 ahead of the listing, said earnings figures showed an increase in total revenues after trading of equities rose. Trading in the bourse's shares starts on Sept. 9. NSE said the value of trades in the fixed income market fell 14 percent from a year earlier to 457 billion shillings. It did not offer an explanation. Pretax profit in the first half of 2013 was 223.7 million shillings. The exchange said that last year's figure benefited from a one-off recovery of bad debt worth 114.9 million shillings. With this one-off figure stripped out from the first-half 2013 earnings, profit before tax in 2014 rose 46 percent. (1 US dollar = 88.7500 Kenyan shilling)