I've been trying to find information/reports on the lenght of newsletters, but I've can't find anything specific to use as proof of concept. Basically, we have a client that puts out a lengthy newsletter each month. Specifically it's 225k and over 2000 lines of code even after I minify about half of it.

The open and click rates aren't bad. The last send we did has a 25% open rate, a 5.88% click rate, and a 1% bounce rate.

I feel like the email size is detrimental though... does anyone have any links to reports or stats on this? Or just thoughts?