(Bloomberg) — Tanker rates could average $35,000 a day next year or $20,000 depending on whether oil storage at sea is maintained or disappears, EA Gibson Shipbrokers Ltd. said.

There were 42 very large crude carriers, or VLCCs, storing crude or oil products at the end of last month, or eight percent of the fleet, and 60 smaller Long-Range 2 vessels, the broker said in a report today.

If that remains constant, supertanker rates should rise 25 percent to $35,000 next year as demand outpaces growth in tanker supply, EA Gibson said. Prices would drop to about $20,000 if storage is unwound in the next several months, the broker said.

"The difference in the cases is immense and although on the face of it may not seem very helpful, it is why we have to monitor storage extremely closely — it will be a key determinant for market direction over the next year," EA Gibson said in the report.