Swayfield is a village and civil parish in the South Kesteven district of Lincolnshire, England. The population of the civil parish at the 2011 census was 316. It is situated just over 3 mi east from the A1 road, 9 mi south-east from Grantham and 10 mi north from Stamford. It has approximately 138 houses.
Swayfield's population is 319 today. 
While unlikely, it is possible the population has not changed in the past eight years. I'm not sure why the system had difficulty with this, as I tried other wordings that it got right. 