As of 4/30/18, 415 of the constituents in the S&P 500 Index distributed a stock dividend to shareholders. There are currently 505 stocks in the index. 

For comparative purposes, since 1980, the highest number of dividend-paying stocks in the S&P 500 Index at year-end was 469 (1980), while the lowest number was 351 (2001 & 2002), according to S&P Dow Jones Indices.

Information Technology and Financials contributed the most to the S&P 500 Index's dividend payout at 16.23% and 13.07%, respectively, as of 4/30/18 (see table).

In Q1'18, the total dividend payments from the constituents in the S&P 500 Index totaled $109.2 billion, up 8.23% from the $100.9 billion distributed in Q1'17, according to S&P Dow Jones Indices. 

S&P 500 Industrials (Old), defined as the S&P 500 minus Financials, Utilities, Real Estate and Transportation companies, had cash and equivalent holdings totaling an all-time high of $1.636 trillion in Q4'17, according to S&P Dow Jones Indices. This indicates that S&P 500 companies have the wherewithal to increase dividend payments moving forward, even without factoring in any of the capital that could potentially be allocated to dividends as a result of the cut in the federal corporate tax rate from 35% to 21% last December (Tax Cuts & Jobs Act), in our opinion.