That was over 31 years ago in 1990.
Today he is 73, and has starred in 49 movies in total, 35 since Die Hard 2 was released.
In Die Hard 2, I think William Atherton looks:
Die Hard 2 scores 6.7 out of 10 on The Movie Database.
William Atherton's first acting role was as 'Johnson' in The New Centurions, released in 1972 when he was 25.