It should be noted a significant reduction in the number of births in 2015 compared to 2013, which amounted to 91.9 thousand people, due to the occupation of part of the country and the difficult socio-economic situation.

The abscissa axis corresponding to the indicator «the number of students who completed nine grades» starts in 2012, which corresponds to the 2003 abscissa axis of the indicator «the number of children enrolled to the first grade».

The graduation of ninth-graders according to the abscissa axis in 2012 and 2013 differs from the «number of children enrolled to the first grade» by 13 thousand people and 12 thousand people, respectively. Thus, on average, for various reasons, 12.5 thousand people who were enrolled to the first grade each year do not finish nine grades in a given year. However, since 2014, the annual number of students who have not completed nine classes of those who entered the first grade since 2005 has increased significantly and averaged 53.2 thousand annually. Prior to the occupation, an average of 12.5 thousand people did not complete nine classes each year. Thus, the annual loss of ninth grade graduates in the education system of Ukraine due to the occupation is 40.7 thousand people (53.2 thousand people – 12.5 thousand people).

The abscissa axis for the indicators «number of students who have completed eleven grades» and «students enrolled to HEI» starts in 2014, while the abscissa axis for the indicators «number of children enrolled to the first grade» starts in 2003. (2014–2003 = 11 years).

The difference between the number of children enrolled to the first grade and the number of students who graduated from 11 classes for the period on the abscissa axis for the indicator «the number of students who completed eleven classes» from 2014 to 2019 varies annually from 181.4 thousand persons to 206.7 thousand persons and on the average makes 188.8 thousand persons. This difference includes students who left after the ninth grade to receive higher education and dropped out altogether. Some of those who will receive higher education will enter the Higher Education Institution to receive a full higher education.

The difference between the number of children enrolled to the first grade and the number of students enrolled to the HEIs in the years 2014–2015 on the abscissa axis differs significantly from the difference in 2016–2019. On average for the years 2014–2015 it is 162.45 thousand people, while for 2016–2019 it is 128.8 thousand people. The first period is two years of adaptation to the conditions of hostilities and losses from the occupation. During this period, students who received higher education in the occupied territories did not always have the opportunity to enter the Ukrainian HEI. In addition, educational institutions that have been relocated from the occupied territories have not yet been able to operate at full capacity. Since 2016, the process of admitting children from the occupied territories to Ukrainian HEIs has been established and relocated HEIs have been adapted, so the annual difference between the number of children enrolled to the first grade and the number of students enrolled to HEI has stabilized at 128.8 thousand at 8 %. Let’s take 128.8 thousand people as a CB constant for further calculations.