Since January 13th.
Sounds good right up until you realise that's over a 3 1/2 month period, and then it seems hardly anything. We walked 35k in 2 weeks in August last year.
I've just got back from another run - 7.2k in about 50min - and it's too slow. When my speed drops below 6min per kilometre impact from each footfall starts to become a problem - instead of bouncing, each foot thumps down, jarring and causing damage. If I can get the speed up, not only will it feel more satisfying but it will actually become more comfortable.