It’s not really about percentages – it’s more about the number of complaints being lodged against your campaigns that matter to ISP's like Gmail, Yahoo and Hotmail.

Every time someone hits the spam button your sender reputation decreases a little more.

So even though your overall spam complaint ratio may be in the green – each and every complaint that ISP’s see made against you adds up to the overall sender profile picture that they’re building for you.

The more complaints they see (not complaints to send amounts) the more they will start to think that you're a spammer.