Updated from 4:30 pm. ET to include list of top ten dividend payers in the S&P 500 by current yield, information about the increase in the index's overall yield. NEW YORK ( TheStreet) -- Nearly 80% of the companies in the S&P 500 paid dividends at the end of the fourth quarter, according to FactSet Research, which said Friday that the total of 393 companies is the highest level since the fourth quarter of 1999. "While the index consistently had greater than 400 dividend-paying companies (or more than 80% of constituents) -- during the 1990's, the 80% milestone has not been breached since the turn of the century," the firm said. "The recent low for the number of trailing twelve month (TTM) dividend-payers was 368 in January 2010. Since that time, dividend-paying companies have grown organically (there has been a net loss of three dividend-paying companies from the thirty-seven constituent changes in the S&P 500 over the two-year period)." Of course, Apple ( AAPL) recently unveiled its plan to join the ranks of dividend payers, announcing on Monday that it expects to initiate a quarterly payout of $2.65 per share "sometime in the fourth quarter of its fiscal 2012." Fittingly, given Apple's announcement, FactSet said companies in the information technology sector have embraced returning money to shareholders in the past decade. "Ten years ago (July 2002), just 17.9% of Information Technology companies in the S&P 500 paid a dividend in the trailing twelve months," the firm said. "However, Q3 2011 marked the first quarter in the S&P 500 in which there were more dividend-paying stocks in the Information Technology sector than non-dividend-paying ones. And, at the end of Q4 2011, dividend-paying stocks in the sector held the strongest majority in over twenty years -- 53.5% of S&P 500 Information Technology stocks paid a dividend over the trailing twelve months." In further sector analysis, FactSet said telecommunication services companies have been lagging in increasing their payouts with only AT&T ( T) and Verizon ( VZ) announcing boosts. "This general reluctance of companies in the Telecom Services sector to increase dividends could be a product of weak earnings," the firm said. "Four of the seven constituents in the Telecom Services sector reported losses for Q4 2011. Overall, the sector reported a loss of -$9.7 billion in the quarter and a profit of only $4.8 billion over the trailing twelve months. This trailing twelve month earnings figure is just over a fourth of the value of trailing twelve month earnings at the end of Q3 2011 ($17.7 billion)."