This year 's S & P 500 Report , produced by PricewaterhouseCoopers , received the highest response rate ever from corporations ( 332 responses , representing 66 % of the S & P 500 , up from 64 % last year ) ; the highest level of disclosed corporate greenhouse gas emissions ( 260 responses , representing 79 % of respondents , up from 73 % last year ) ; a sharp spike in companies reporting emissions reduction targets ( 169 responses , representing 52 % of respondents , up from 32 % last year ) and the greatest level of detail to date .