Someone over a Reddit post numbers going back each year for a few years. According to his numbers in 2013 the number of congregations closed went way up to 62 and continued to rise and the last couple of years well over 100 per year. Don’t know where he got his info from. He’s says it may have to do with changes of each congregations legal status and possible reductions from the LDC.
He also just posted that his sources are research in Germany of closed halls. Info provided at JW.borg and other official sources. He lists a German website as well of I believe all the sold halls. The website listed is https://www.jehovaszeugen.de/amtsblatt.44.0.html