Swing vs. trend

[SingingAnalyst]

Can someone please explain the difference between a swing and a trend, at least for the purposes of this site? I fear I have been misusing these terms.

[Bidenworth2020]

a swing is just the change in margin. For example, if I won a race by 10 points against an incumbent who won by 10 in the last election, that would be a 20 point swing. A trend is how much a place swings compared to the overall swing. For example, if I won a county by 5 when the previous opponent won it by 3 but lost the race by 10, that would be an 18% trend towards my opponent. Does that make sense?

[Adam Griffin]

In Atlas definitions, swing is the change in D-R margin in an area relative to the last election; trend is difference between the swing of said area and the swing of the nation.

Example: ABC County voted for Romney by 10 in 2012 and for Trump by 5 in 2016. ABC County swung 5 points to Clinton.

However, the nation as a whole voted for Obama by 4 in 2012 and for Clinton by 2 in 2016. The nation swung 2 points to Trump.

Since the nation swung 2 points to Trump and ABC County swung 5 points to Clinton, the trend of ABC County would be 7 points in favor of Clinton: the difference between the two shifts.

It's worth noting that "trend" in this context can be used to apply to statewide contests and in presidential elections at the state level as well; one might compare the swing of a county in a gubernatorial election to the swing of the state overall, or might even compare the swing of a congressional district to that of a state in a presidential contest. However, the original definition above this paragraph is the official Atlas definition of trend.

[SingingAnalyst]

Thank you!

At the risk of further confusion, I tend to think of a "swing" as a one-time event, whereas a "trend" can stretch over several election cycles.

What you both said makes perfect sense, though.