The shortfall of school places is calculated by comparing the existing capacity of schools with year-on-year forecast of pupil numbers.
For the purposes of school place planning and the allocation of capital funding, it is important to examine the extent to which pupil growth translates into demand for additional school places. In some areas surplus capacity is able to absorb some of the growth in pupil numbers, whilst in other areas new school places will be required.
Our analysis of the overall school places shortfall (ages 5 to 16) compares existing capacity against forecast pupil numbers, with appropriate adjustments for new Free Schools. Further details about the methodology used are available in Appendix 1 of the full document.
A total of 110,364 new school places will be needed in London between 2016/17 and 2021/22 to meet forecast demand, consisting of 62,935 primary places and 47,430 secondary places (see below). This is equivalent to creating 3,680 additional classes across London at an average rate of 600 new classes every single year. 
Breakdown by borough
These interactive maps show the shortfall as a percentage of 2016/17 capacity by borough.
 Assumes class sizes of 30 pupils