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Are you for reals? The chart tells you the size of the adjustments. And yes, that includes the 2012 changes.With respect, your chart has absolutely nothing related with the topic of changing the published temperature data.
More importantly: Steven Goddard = Epic Fail
Q. Why are the US mean temperatures in the Hansen 1999 paper so different from later figures?
A. In the Hansen et al. (1999) paper the GISS analysis was based on GHCN data alone; in the meantime, the group working at NOAA/NCEI had taken a closer look at the US data, an investigation that resulted in substantial modifications compensating for station moves, procedural changes, etc. These corrected data were made available as "adjusted USHCN" data. The adjustments and their effects are described here, with a graph showing the effect of each of the five individual adjustments here. These adjustments caused an increase of about 0.5°C in the US mean for the period from 1900 to 1990. They had no significant impact on the global mean. About half of that increase was due to information obtained about station moves (mostly from cities to airports where conditions were generally cooler), the other half from changes in the time of observation (mostly as a consequence of a concerted effort to transition to a uniform time of observation for a whole network of stations). After 1999, GISS replaced the unadjusted USHCN reports by the adjusted reports, and reported on the differences this made in Hansen et al. (2001). A list of all changes to the GISS analysis and their impacts is presented in the History Section. (Emphasis added)
Data.GISS: GISTEMP -- Frequently Asked Questions
As a reminder, The US is only 2% of the planet's surface area. Thus, no intelligent person should be surprised when the global impact of the change is small.

Data.GISS: GISTEMP HISTORY
I strongly recommend you stop hanging your hat on cherry-picking denier blogs.