It feels to me like DLM has "banded" your connection, limiting you to a maximum speed of 35Mbps down and 6Mbps up; the modem has synced at almost precisely this speed. If DLM has chosen to do this, then it has seen lots of errors on your line - and the errors have likely survived through lesser levels of intervention. "Banding" (setting an artificial limit on the speed) is one of the more drastic steps that DLM can choose.
We can see a lot of CRC errors (aka OHF errors) - which can be seen in two ways: a) large bursts around 8-9am and 6pm-10pm, and b) a constant stream of low-level errors. Between both types, these CRC errors cause large amounts of "errored seconds" - which is what DLM monitors when deciding to intervene. It suggests your line has been suffering from these in a very bad way, given that you are still seeing these even with such a high level of DLM intervention in place!
I don't think MyDslWebStats is getting complete details from your modem about the DLM intervention (it isn't showing anything about interleaving, FEC settings, INP settings or G.INP retransmission data), so we can't add much more to this analysis. However, we can see that DLM has intervened in other ways, because you are getting lots of FEC errors in the same way you are getting lots of CRC errors - and FEC errors only occur after DLM has intervened in ways other than "banding".
It appears you are suffering from high levels of interference. The pattern of the biggest bursts of errors would make me suspect central heating as the cause of those. The others are more constant, and would need much more work to figure out; unfortunately, the pattern there is somewhat masked by the large bursts.
