<p>For future reference, we can rule out downvotes, because those show up in <a href="https://stats.stackexchange.com/users/27403/quantibex?tab=reputation">your reputation score history</a> ordinarily. The <code>-4</code> you noticed does not appear when I look at your rep score history, but I can usually see a <code>-2</code> on my own history when a user or post was removed. This is a loss of <code>+2</code> rep that you originally gained by suggesting an accepted edit. It hurts much more when a user gets removed who had upvoted several of your posts, or when serial upvoting is automatically reversed: then you lose <code>+5</code> per question upvote and <code>+10</code> per answer upvote! See the relevant meta-controversy:<br>
"<a href="https://meta.stackexchange.com/q/125740/246931">Don't throw away all votes when a user is deleted</a>." <sub>(<a href="https://stackoverflow.com/users/616736/lorem-ipsum?tab=reputation">The SO user formerly known as Yoda</a> once lost 1685 rep!)</sub></p>

<p>My guess as to why you're unable to see the two entries on your own rep score history is that you haven't checked the box on the bottom left that shows these (see inside <a href="https://meta.stackexchange.com/a/19775/246931">obligatory freehand circle</a>):</p>

<blockquote>
  <p><img src="https://i.stack.imgur.com/4VVmD.png" alt="Stack Exchange loves some freehand circles..."></p>
</blockquote>

<p>BTW, losses also occur when a post gets migrated, but you gain your vote reputation back at the destination site. Sadly, the same is not true of suggested edit reputation gains (else I'd be rich on SO). Then again, one meta-post (<a href="https://meta.stackexchange.com/q/125787/246931">Points for answer migrated with question, points for edit not migrated</a>) suggests something I can't explain: he kept his suggested edit gains on Server Fault post-migration. This has not been the case for my suggested edits to questions asked here on CV that got migrated.</p>
