Hi @kayawalton,
I have to have them as a segment to get it at the visit level and also because I have multiple old and new urls that count as the same page, so I can't use just the dimension prop or evar item. In that case, which is the one I should use? Both given completely different values and I don't understand the difference. Time Spent per Visit (Seconds) seems incredibly higher compared to Average Time Spent on Site (Seconds).
cc @jennifer_dungan
Got it. So let me walk back a couple of things I've said (I love time metrics in Adobe Analytics, but sometimes they require a bit of thought process):
I would use Time Spent per Visit on your table. It captures most of the session duration because it calculates the difference between the timestamp of the visit's first hit and the timestamp of the visit's last hit (Total seconds spent) AND divides the total time by the number of visits (minus bounces) that apply to that segment.
The Average Time on Site is a bit of a misnomer because it uses unbroken sequences as the denominator. Depending on your visitor flow, there could be more than one sequences triggered by the dimensions in your segment during one visit, which is why the Average Time on Site is lower than Time Spent per Visit.
Adobe considers these two metrics similar, but I think their intended use is very different. Time Spent per Visit is meant to look at complete sessions (like in your case), while Average Time on Site is more for when you are looking for more granular time data (such as specific times spent on a particular page or dimension).
Phew, hope that clarifies the difference!