Charter advertises 60 megaBITS per second... and you are downloading at 2.5 megaBYTES per second... that IS consistent with having a 22megaBIT connection, so speedtest is not Lying - and I dont think Charter is either.
HUH? WHAT!... here's why:
8 bits in 1 byte, plus some network overhead... its really crude, but comes out very close to 10 / 1 ... this means that you can take a number that the ISP advertises and divide it by 10, and roughly that will tell you the download rates you can expect to have....
In your case this should be alot closer to 6.0 then to 2.5
However, no one these days will GAURANTEE you bandwidth - the service is always offered on "best effort" terms. (Shoulda really read those 5 pages of fine print) So in truth, if everyone on your block stopped downloading for a day - you WOULD see your full bandwith cap up to 60megabit...
But since the ISP's network appears to be over-saturated, that is not the case.
This is all assuming of course that someone on your network is not mooching your bandwidth behind your unsuspecting back, or that possibly your aged router simply cant handle that much bandwidth. To know for sure plug 1 computer directly into the back of the modem, adjust settings as needed to get a connection, and re-run your speed test.