Unloved Advertising in E-Mails
A survey by Statista found out that 26.8 percent of all American respondents thought ads in newsletters were very annoying. Another 48.5 percent of respondents thought that those ads were either 'not too' or 'kind of annoying'. So, counting together all of the annoyed you're talking about 3 in 4 people who could do without ads in e-mail newsletters. Only 12.2 percent of respondents weren't annoyed at all.
This chart shows consumer's level of annoyance related to advertising in e-mail newsletters (in percent)