A Minnesota company is adding a rider to the variable annuity benefit guarantee market.

Ameriprise Financial Inc., Minneapolis, says its IDS Life Insurance Company and IDS Life Company of New York units will be selling a new guaranteed minimum accumulation benefit rider with RiverSource family variable annuities.

Customers can buy the GMAB rider with the RiverSource Retirement Advisor Advantage Plus variable annuity contracts and with the RiverSource Retirement Advisor Select Plus variable annuity contracts, Ameriprise says.

During a 10-year waiting period, the new rider “provides a one-time adjustment to the contract value equal to the greater of initial purchase payments or 80% of the highest contract value on any contract anniversary,” Ameriprise says.

When the waiting period is up, the benefit may help purchasers in a down market. But, if the value of the variable annuity ends up exceeding the value of the original investment, or greatest lock-in value, the accumulation benefit will provide no additional monetary value, Ameriprise says.

Investors who buy the accumulation benefit rider must use an asset-allocation program run by a unit of Morningstar Inc., Chicago.

The Ameriprise IDS Life units are responsible for backing the rider guarantees.