A transport company purchased a truck for $40,000. The operating cost was $3,800 per month, with average revenues of $5,500 per month. The truck was sold for $12,000 after two and a half years. The company's actual rate of return was closest to:

- 2.7% per year

- 2.7% per month

- 32.5% per year

- 32.5% per month