I can't give you a percentage, my wash can be closed up to 60 days due to winter weather so reserves are important. 6 months of operating expense work for me. That includes property taxes. Hope that helps.
Even if ... not closed ...during an extremely bad weather winter like this winter here in parts of North Dakota ... income both gross & net for some of us up here in colder climates would tend to throw futuristic projections off! We are finally getting a bit of low 30s F° temperatures to start some melting of the early November-December's 60+ inches of local snow-pack.
We rely on the city being generous with their
"beet juice"! During a Q&A of one of our recent 12 sessions of our 2023 local Citizens' City Govt Academy of which I am part of ... us group of 20 citizens were told it has been a bit too cold for the "beet juice for streets" to work properly this specific winter!
I am not sure about the salt-sand-type of juice other localities use!!!???