Monthly distribution of the density and intensity of coronal off-limb structures from 1 January 2011 00:00:00 to 31 December 2021 21:00:28 UT. The structures were recorded at three-hour intervals, and the total number observed each month is displayed on the y-axis. Each dot represents the total number of observed structures per month, with the size and colour of the dots indicating their intensity. Smaller and lighter dots correspond to weaker summed intensities, while larger and darker dots represent higher summed intensities. The intensity and number of detected structures are correlated. A peak in both density and intensity occurs in 2013, while the overall trend shows a sharp decline throughout SC 24, with a slight increase at the beginning of the next cycle around 2019–2020.