Physical vs economic occupancy, explained
Occupancy is the number every owner checks first. But "90% occupied" can hide a facility that collects 75% of what it could. Physical occupancy tells you how full you are. Economic occupancy tells you how much of your potential rent you actually collect. You need both.
Physical occupancy
Physical occupancy measures how much of your space is rented. You can count it two ways.
- Unit occupancy: occupied units divided by total rentable units.
- Square foot occupancy: occupied square feet divided by total net rentable square feet.
Square foot occupancy is the better measure. A facility can have many small units rented and large units empty. Unit occupancy would look high while most of the building sits vacant.
Large operators report square foot figures. Public Storage, for example, reports weighted average square foot occupancy in its annual 10-K.
Economic occupancy
Economic occupancy measures how much rent you collect against what the facility could earn. The usual formula is actual rental income divided by gross potential rent.
Gross potential rent is what you would collect if every unit were rented at current street rate. Some operators use the in-place rate for occupied units instead. Pick one definition and keep it.
Public companies report a related measure. Public Storage defines realized annual rent per available square foot as rental income, before late charges and fees, divided by average available square feet. It is a revenue-per-foot cousin of economic occupancy.
Economic occupancy falls below physical occupancy when you have:
- Tenants paying below street rate, often long-term tenants never raised.
- Move-in discounts and free-month specials.
- Delinquent rent you have billed but not collected.
- Units used by staff, held for repairs or comped.
It can rise above physical occupancy when existing tenants pay more than current street rate. That happens after rate increases when street rates are falling.
Worked example
Second step: what closing the gap is worth
The lesson: judge pricing and collections changes on collected rent, not on physical occupancy alone. Run the same arithmetic with your own rent roll before a rate increase.
What the gap tells you
A large gap with high physical occupancy usually means pricing, not demand. You are full but cheap. Look at rate increases for long-term tenants and at move-in specials.
A large collections slice means a delinquency problem. Tighten your late-fee and lien process. See handling delinquent tenants.
Low physical occupancy with a small gap means a demand or marketing problem. Your rates are holding, but not enough people are renting.
| Physical | Gap to economic | Likely issue | First move |
|---|---|---|---|
| High | Large | Underpriced in-place rents | Review rate-increase program |
| High | Small | Healthy, maybe underpriced street rate | Test higher street rates on full unit types |
| Low | Small | Weak demand or visibility | Marketing, online listings |
| Low | Large | Discounting to fill and poor collections | Fix collections, then pricing |
Occupancy during lease-up
A new facility starts at zero physical occupancy and climbs. Economic occupancy climbs more slowly, because early tenants are often won with specials.
Track both from the first month. The physical line shows whether demand exists. The economic line shows whether you are buying that demand too cheaply.
Once physical occupancy on a unit type stays high for several months, start raising its street rate. Then begin a measured increase program for long-term tenants on that type.
Lenders on construction or bridge loans often set covenants on occupancy or debt service. Ask whether those covenants use physical occupancy, collected revenue or both. A facility can meet one and miss the other.
Write down the date each unit type reached stabilization. Buyers and lenders will ask, and the record supports your projections at refinance.
Unit occupancy vs square foot occupancy
The two physical measures can diverge sharply. Picture a facility where every 5x5 and 5x10 is rented but half the 10x30s are empty.
Small units are many in number but small in area. Large units are few in number but large in area. Unit occupancy will look strong while square foot occupancy lags.
Square foot occupancy is closer to revenue, because rent scales roughly with size. That is why public operators report it.
Still, track both. A gap between them tells you which sizes are not renting. That points to a unit mix or pricing problem on specific sizes.
How to track both each month
- Pull occupied and total square feet from your management software on the same day each month.
- Write down the gross potential rent definition you use and keep it fixed.
- Record rent billed and rent collected separately.
- Compute physical, economic (billed) and economic (collected) occupancy.
- Track the gap by unit type, not just facility-wide.
- Compare against the same month last year to remove seasonality.
When you compare yourself to published benchmarks, check which occupancy they report. REIT figures are typically square foot physical occupancy for stabilized facilities. More benchmarks are in self storage industry statistics.
Common mistakes
- Quoting unit occupancy to a buyer or lender who expects square foot occupancy.
- Counting company-use or damaged units as rentable in one month and not the next.
- Calculating economic occupancy on billed rent and calling it collected.
- Changing the street rate used for gross potential rent mid-year without noting it.
Buyers will recompute these numbers from your rent roll. If you are selling or buying, see buying an existing self storage facility.
Frequently asked questions
Which occupancy number should I report to a lender?
Ask which definition they want. Most expect square foot physical occupancy plus collected revenue from your financial statements.
Is a big gap always bad?
Not always. During lease-up, discounts widen the gap on purpose. It becomes a problem when it persists after stabilization.
Can economic occupancy be over 100%?
Rarely, if in-place rents exceed street rates across a nearly full facility. It is a sign your street rate may be too low.
Do company-use units count as rentable?
Pick a rule and keep it. Many operators exclude them from rentable space and note the count separately.
What if rate increases cause move-outs?
Some move-outs are expected. Compare the collected rent gained with the rent lost, as in the second worked example, before deciding.
Should I use street rate or in-place rate for gross potential rent?
Street rate shows what the market would pay today. In-place rate hides below-market tenants. Street rate is more useful for spotting lost revenue.