The t-belt interval is 70k miles up to 1998.

1999+ is 105k miles.

The newer cars might be even longer?

A couple of finer points are required:

- those numbers are for 'ideal' duty, not what the manufacturer considers 'severe' duty. 'Severe duty' is generally defined as short trips, dusty conditions, humid conditions, very hot or very cold,.... basically the way EVERYONE drives. The Haynes manual suggests nearly halving the interval for severe duty (on the older belt system from 70k to 45k), but I think that's a bit conservative. To stay on the better side of this rule I would chop at least 5k miles off this interval.

- The early 'manual tensioner' systems on the 1999 esp failed early a high percentage of the time. If you still have the original tensioner on there, the interval should be cut short to ~70k again. This shouldn't be a problem though because all of those tensioners should have been replaced based on age alone by now (10 years is generally seen as the max lifespan for t-belt)
--
1998 V70 AWD->FWD Turbo 200k+