Occupancy is booked nights divided by the nights in the period. For a full year, that denominator is 365 -- not 365 minus the dates your calendar shows as blocked. The second version is the one most owners are handed, and when we measured it across the 44 doors Simple Lyfe Stays manages in western Michigan, it turned out to be wrong in a specific and expensive direction.
Here is the finding that changed how we report the number. In our trailing-twelve-month pull ending 2026-09-23, 776 booked nights sat inside block records, spread across 17 of the 43 doors that carried any block at all. A blocked date on a rental calendar is frequently not a date the property was unavailable.
What is the occupancy formula for a short-term rental?
Occupancy is booked nights divided by nights in the period, times 100. In the twelve months ending 2026-09-23, the portfolio booked 5,727 nights across 1,554 reservations on 44 revenue-producing doors in Newaygo, Lake, Mason, Oceana, Mecosta, Kent and Muskegon counties. Every per-door occupancy figure in that report uses a flat 365-night denominator with no adjustments.
The formula is not the hard part. The denominator is.
Should you subtract blocked dates from the denominator?
No. Subtracting blocked nights assumes a block record proves the property could not be booked, and on real data it does not. One door in our portfolio carried a single block record running from September 2025 to January 2027 -- covering every night of the measurement window -- and took 39 reservations and 142 booked nights inside it. A second door carried a 392-night block and booked 252 nights inside that. A third was covered essentially all year by two overlapping blocks and still booked 135 nights.
If you subtract those block days from the denominator on any of those three doors, you get an occupancy rate above 100 percent, or you quietly drop real nights to avoid one. Neither number means anything.
Why doesn't a blocked date mean the property was unavailable?
Because "block" is one generic record type covering several unrelated situations. OwnerRez returns an owner's week at the lake, a furnace replacement and a hold left over from a renovation as the same kind of record, with no sub-type separating one from another. We wrote about what that means for owners taking their own dates -- your stay and a maintenance hold look identical in the data.
Then add the holds nobody ever removed. A block set for a renovation or a possible sale can outlast the reason it was created, and the door goes right on taking reservations around it. The record survives; the condition it described does not.
What is the only reliable way to tell a property was dark?
Zero realized bookings inside the interval. Check the outcome, not the flag. If a door took no reservations at all across a stretch of calendar, that stretch was genuinely dark, and it is worth asking why. If it took bookings, it was live, whatever the calendar said.
One more caution from the same pass, because it is the easy mistake: do not add block days together. Overlapping block records count the same calendar day twice. Our own first pass summed them and overstated one door by 211 nights and another by 152 before we switched to counting each distinct date once.
What should you compare your occupancy rate against?
Only a door measured the same way, in the same window, in the same cohort. Three cases break a straight comparison, and all three exist in our portfolio right now.
Seasonal doors close for winter, so their annual rate is a seven-month number sitting on a twelve-month denominator. Doors under a year old have not seen a full season cycle, so they have no comparable annual rate at all. And a listing whose calendar is linked to a second unit can show no bookings of its own while real stays land on the twin's ledger -- a zero there is a bookkeeping artifact, not a dead property.
Two of our doors show what a clean comparison looks like: Indian Lakes Hideaway in Sparta, Kent County, a 3-bedroom, 1-bath house, and Little Blue Lake Cottage in Greenville, 3 bedrooms and 2 baths, sleeps 6. Both are year-round, both are their own calendar, both have been in the portfolio long enough to measure. Their occupancy numbers are comparable to each other. Neither is comparable to a door that shuts for the winter.
What should you ask your property manager?
Ask for three numbers and one date: booked nights, reservation count, and the denominator used, for a stated window. If the report gives you a percentage without those, you cannot tell whether it was computed honestly, and you cannot compare it to anything.
A good manager will also tell you which of your empty nights were a choice. That is the difference between a calendar that looks full and a property that earned. If you want that read on your own place, our property management team does this measurement for every door we run, and we are glad to walk an owner through their own numbers before anything is signed.
Figures are portfolio-level counts from a live OwnerRez pull on 2026-09-24, covering arrivals from 2025-09-24 through 2026-09-23. They describe the doors Simple Lyfe Stays manages in western Michigan and are not a market forecast.