So what is the problem with asking the company?
They do have the details, after all.
I could call my DM tomorrow and simply ask... What are my total miles since I started here?
She would look at a certain screen and tell me... You have driven x miles as of this date.
That date would be within a few days of today.
If you are not a good record keeper like me, and you just want a guesstimate quickly, just average it all out.
Driving an average of 2000 miles per week for 48 weeks per year is about 100,000 miles. 3000 miles for 48 weeks per year is about 145k miles per year.
That's assuming you are driving everyday for about 3 weeks out of the month. The last week will be your resets and hometimes. That's 48 weeks of driving per year out of 52 total weeks. That's easy to remember because there are also 52 cards in a full deck.
You wont be spot on, but you can ballpark it and probably get fairly close with honest averages. It will only take you a few minutes.
So if you can manage 3k miles every week average for 48 weeks in the year, that's about 80k at .55 cpm without accessorial pays. 2000 miles per week for 48 weeks is 55k gross, maybe a little less.