One of the most important metrics in banking is the efficiency ratio, which is generally viewed as a measurement of how carefully a bank spends money. Following this definition to its logical conclusion, the more parsimonious the bank, the lower its efficiency ratio should be.
But this common understanding fails to capture the true nature of what the efficiency ratio actually measures. It is in reality a fraction that expresses the interrelationship between the two most dynamic forces within any business organization: the growth of revenue and expenses.
Looked at this way, the efficiency ratio is actually a measurement of effective spending—how much revenue does every dollar of spending produce. And embedded within the efficiency ratio is a simple but extraordinarily important concept that is the key to high profitability—positive operating leverage.
But first, let’s look at how the efficiency ratio works. It’s an easy calculation. The numerator, which is the top half of the fraction, is expenses. And the denominator, which sits below it, is revenue. A bank that reports $50 of expenses and $100 of revenue in a quarter has an efficiency ratio of 50 percent, which is the benchmark for most banks (although most fall short).
However, not all 50 percent efficiency ratios are created equal.
Consider two examples. Bank Cheapskate reports $40 of expenses and $100 of revenue in its most recent quarter, for an efficiency ratio of 40 percent. Coming in 10 percentage points under the benchmark rate of 50 percent, Bank Cheapskate performs admirably.
Bank Topline reports $50 in expenses and $125 in revenue in its most recent quarter. This performance also results in an efficiency ratio of 40 percent, equivalent to Bank Cheapskate’s ratio. Again, an impressive performance.
While the two ratios are the same, it is unlikely that most institutional investors will value them equally. The important distinction is how they got there.
The argument in favor of Bank Cheapskate’s approach is simple and compelling. Being a low-cost producer is a tremendous competitive advantage in an industry like banking, which has seen a long-term decline in its net interest margin. It allows to a bank to keep deposits costs low in a tight funding market, or back away from an underpriced and poorly structured credit in a competitive loan market. It gives the bank’s management team optionality.
The case for Bank Topline’s approach is probably more appealing. Investors appreciate the efficiency of a low-cost producer, but I think they would place greater value on the business development skills of a growth bank. In my experience, most investors prefer a growth story over an expense story. Bank Topline spends more money than Bank Cheapskate, but it delivers more of what investors value most—revenue growth.
To be clear, the choice between revenue and expenses isn’t binary—this is where positive operating leverage comes in.
Positive operating leverage occurs when revenue growth exceeds expense growth. Costs increase, but revenue increases at a faster rate. This is the secret to profitability in banking, and the best management teams practice it.
A real-life example is Phoenix-based Western Alliance Bancorp. The bank’s operating efficiency ratio in 2018 was an exemplary 41.9 percent. The management team there places great importance on efficiency, although the bank’s expenses did rise last year. But this increase was more than offset by strong revenue growth, which exceeded expense growth by approximately 250 percent. This is a good example of positive operating leverage and it’s the real story behind the bank’s low efficiency ratio.
The greater the operating leverage, the lower the efficiency ratio because the ratio is relational. It is not solely a cost-driven metric. At Western Alliance and other banks that focus on creating positive operating leverage, it’s not just how much you spend—it’s how many dollars of revenue each dollar of expense creates.
To understand the real significance of a bank’s efficiency ratio, you have to look at the story behind the numbers.