I did not gain or lose. That won't happen until I buy or sell
Or you move out of the country (though since US taxes on citizenship, may not apply). For Canadians, if you emigrate, you have to "pretend" to sell off everything and pay capital gains based on the date you left Canada. So, during a correction (to the Canadian markets) is a good time to move.
Like others, I didn't bother to look. I'm in the long (ish) haul, so I worry about trends and try not to panic over small tips (or get too excited about small jumps).