What am I looking at?
Instead of looking at season-long averages, this chart shows only the most recent games. This more accurately shows if a team is recently playing well or poorly, and if it's their offense or defense (or both?) that is the reason for their recent play. Good teams will show their 'Goals For' to be higher than their 'Goals Against', and the larger the gap between those lines, the more lopsided the wins (or losses) have been.
When Edmonton was on their winning streak in 2023-24, they were averaging 3 to 4 goals per game on offense, which is good, but their defense was the difference, only giving up 1.5 goals per game for a long stretch (see their chart, on/around their 40th game). In that same season, Toronto went on a winning streak around game 50, and their chart shows that all of that was offense-driven. Also in that same season, Vegas started the season with a winning streak, averaging 4 goals a game but also only allowing under 2 goals per game for the first two weeks of play, so credit both sides for that streak.
All goals are counted, including power plays, short-handed, and empty nets.

What am I looking at?
When a team wins, it gets 2 standings points. An overtime loss is 1 point. Charting that data alone, as-is, makes it look like a team might be doing well when it isn't. Getting 1 point per game would be an upward-pointing chart, when really, 1-point per game is just breaking even. A loss would be a flat line, when it really should visually indicate something bad.

Instead, I put this unique chart together in 2017 when the Golden Knights started playing, as a better way to show how a team is trending. Wins trend the team up, losses trend them down, and overtime losses show as a flat line. It's used routinely in baseball, where this is a regular statistic. Using it in hockey really shows teams that are doing well, or poorly, hot or cold, etc.