If I'm reading your bill correctly your greatest usage seems to be in the Winter months going higher or lower month-to-month based upon the average outside temperature for those months and except for a spike in September your usage is lower in the warmer months.
That should be at least good clue. Especially since you live in an area, Campbell CA, that has warm summers and mild winters. A/Cs especially central AC is far and away the biggest electricity hog. So for a house in Campbell one would expect your usage to be the exact opposite of what it is in a typical Campbell residence.