In 2001, median pay in film and TV was roughly the same: $108,000 in TV, $105,000 in film. By 2014, the last year available, median TV writer earnings had grown to $138,000, while median film writer pay had dropped to $77,000 (all in 2021 dollars). Meanwhile, the number TV writers has increased dramatically, while the number of film writers has remained almost flat. (Some writers work in both mediums, so the total number of working writers is less than the sum of TV and film writers.)
Source: Is Writer Pay Up or Down? Depends How You Look at It