It's the day the crop reports come out.
4 seconds sound clip from the Trading places (1983) movie soundboard.
You can hear this line at 00:22:01 in the Blu-ray version of the movie.
Quote context
[...]
- January 2nd, is that good for you?
- Oh, heck. 2nd January. Can't do it.
- It's the day the crop reports come out.
- What do those stupid old crop reports have to do with Mumsie's party?
- It's the busiest time of year in the office, sugar-puff.
- Why can't you make them do it another day?
- Oh, no. The Department Of Agriculture gets those estimates from all over the country.
[...]