The figure given here is an estimate for July 2003. If the population of Russia was 145.2 million in the 2002 census, one might assume it would have been higher than 144,526,278 in July 2003, based on annual growth.
However, the population growth rate of Russia was estimated at minus 0.3 percent in July 2003. Given that this probably wasn’t just a single-year blip but part of a long-term trend, it would be reasonable to assume that the growth rate was the same the previous year.
This negative growth rate would mean a drop of 435,600 people 2002 to 2003. If we subtract this number from the 2002 total, the result would be 144,764,400, statistically close enough to the figure given here to consider it as a close estimate of the number of Russians.