Just found this excellent presentation about investing in the Forex market.
Accounting leverage is total assets divided by total assets minus total liabilities.
Notional leverage is total notional amount of assets plus total notional amount of liabilities divided by equity. Economic leverage is volatility of equity divided by volatility of an unlevered investment in the same assets. To understand the differences, consider the following positions, all funded with $100 of cash equity.
- Buy $100 of crude oil. Assets are $100 ($100 of oil), there are no liabilities. Accounting leverage is 1 to 1. Notional amount is $100 ($100 of oil), there are no liabilities and there is $100 of equity. Notional leverage is 1 to 1. The volatility of the equity is equal to the volatility of oil, since oil is the only asset and you own the same amount as your equity, so economic leverage is 1 to 1.
- Borrow $100 and buy $200 of crude oil. Assets are $200, liabilities are $100 so accounting leverage is 2 to 1. Notional amount is $200, equity is $100 so notional leverage is 2 to 1. The volatility of the position is twice the volatility of an unlevered position in the same assets, so economic leverage is 2 to 1.