Volunteering is an unique resource of nonprofit organisations compared to the public and market sectors, it is an essential, necessary but certainly not sufficient condition for their operation, altough its actual weight and value Iis not easy to estimate. In this paper, we show how the Central Statistical Office's survey of nonprofit organisations has attempted to measure the extent of this in-kind contribution, both in time and, in money, over the last 25 years with the help of statistical tools, and what methodological problems it has faced and continues to face during the organisational data collection. All this in order to try, also in this context, to show the negative impact of the coronavirus epidemic that started in 2020, by assessing the extent of financial and human resources support that NGOs could hope from the public - despite thier more intensive participation and activity expected by the society.

Keywords: nonprofit organisation statistics, measurement of volunteering, formal volunteering, content of volunteering, volume of volunteering, value of volunteering,