Here are the financials for Australia since 2013.
The last couple of years has seen a big drop in donations, from around $25- 30 million to $8 - 10 million per year.
https://www.acnc.gov.au/charity/charities/77f70f2a-39af-e811-a963-000d3ad244fd/documents/
This from Canada:
About Watch Tower Bible and Tract Society of Canada:
Watch Tower is a 0-star charity with Low demonstrated impact. The charity does not have a website and reports very little about its $30m programs and their results. Watch Tower has large funding reserves and is not financially transparent.
For every dollar donated, 99 cents go to the cause, which is outside Ci’s reasonable range for overhead spending. When a charity reports overhead spending of less than 5%, it sometimes suggests that the numbers are inaccurate or misreported.
https://www.charityintelligence.ca/charity-details/40-watch-tower-bible-and-tract-society-of-canada