Trees had been cut at unsustainable rates for decades without efforts to restore the forests.

The human population is growing at an unsustainable rate of 8% per year (1995).

Opponents say that Medicare, already growing at an unsustainable rate, cannot afford to pay for "lifestyle drugs."

"Well before it reached a billion people, India was using water at an unsustainable rate," he said.

However, the aquifer is being depleted at an unsustainable rate in the long term.

The pre-1914 arms race was consuming increasingly larger portions of national budgets at an unsustainable rate.

Consumers have been spending much of their income at an unsustainable rate.

Upon receiving his full inheritance he set about spending it at an unsustainable rate.

Essentially, the problem can be expressed very simply: aviation is growing at an unsustainable rate.

At the same entitlement spending is growing at an unsustainable rate.