I have attached a longer sampling of the data as per your needs.

It does get better during sleeping hours as suspected.
The ISP backbone consist of 3x T3 (45Mb@ or total 135MB) as connection. Their customer base is about 3000-4000 subscribers. Many subscribed at the cheaper 128kbs(down)/64kbs(up), but are actually receiving about 1-3MB speeds if working properly. Although there are several price/speed packages, it appears that every customer is getting the same speed. Higher priced plans sometimes are even slower than the smallest plan.

If you need a complete 24 hours sample set, I can have this posted on a website for your download and further analysis.

Thanks for your expert comments