Deviation of the estimated number of learners in general secondary school from the actual is given in column 8 of **Table 1.6** from 2015 to 2019. We will not take into account the deviation that took place in 2015, as it was a transitional year in which the education system of Ukraine was adapted to the conditions of alienation of the territory of Crimea and parts of Luhansk and Donetsk regions. Then the average value of CBC will be equal to 11.6 thousand people. This constant is used in the calculations of the projected number of students in general secondary schools for 2020–2026 (column 7, **Table 1.7**). Formula (1.5) is used. The calculated contingent of secondary school learners (column 6, **Table 1.7**) is calculated by the formula:

where *CCO*(*t*) – calculated contingent for *t* = 2015–2019; *ACO*(*t*–1) – the actual contingent of students of secondary school in the previous year; *E*1*G*(*t*) – enrolled children in the first grade in a given year; *C*9*G*(*t*) – received a certificate of basic general secondary education (graduated from 9^{th} grade); *C*11*G*(*t*) – received a certificate of completion of general secondary education (graduated from 11^{th} grade); *CE*10(*t*) – continued education in 10^{th} grade.

The projected contingent of secondary school learners (*EC *^{*}) (column 7, **Table 1.7**) for 2020 is calculated by the formula:

The projected contingent of secondary school learners (*EC *^{*}(*t*) – column 7, **Table 1.7**) for 2021–2026 is calculated by the formula:

According to **Table 1.7** build a graph of the dynamics of the actual contingent of secondary schools from 2005 to 2019 and the forecast for 2020–2026 (**Fig. 1.10**).

In fact, the loss of Crimea and parts of Donetsk and Luhansk regions led to a decrease in the number of secondary schools learners in 2014 by 447 thousand people. From 2015 to 2019, this contingent gradually increased from 3,783 thousand people to 4,138 thousand people. And according to the forecast, in 2020 it will reach its maximum and will amount to 4,172.0 thousand people, which is 32.0 thousand people less than in 2013 before the war. The growth of the se condary schools contingent is mainly due to the increase in the birth rate in 2002–2008. In addition, the growth of the secondary schools contingent is explained by the inclusion in this contingent of children of migrants from the Crimea, Donetsk and Luhansk regions.