But, a recent paper by my new LBS colleague Taylor Begley points to an important additional cost of corporate credit ratings - and one that arises even if ratings are perfectly accurate. Companies may engage in short-term behavior to achieve a particular credit rating. This problem arises because credit ratings are discrete categories (e.g. AAA, AA+, BB) rather than a continuous number (e.g. 93.2, 87.8). Thus, a company has a strong incentive to just get into the AAA- category than be at the top of the AA+ category.
In turn, a major driver of credit ratings is a company's financial ratios. For example, for firms with an excellent business risk profile, a Debt/EBITDA ratio of 1.5-2.0 typically leads to a rating of AA; a ratio of 2.0-3.0 typically leads to a rating of A. For firms with a fair business risk profile, a Debt/EBITDA ratio of 1.5-2.0 typically leads to a rating of BBB-; a ratio of 2.0-3.0 typically leads to a rating of BB+ (which is below investment-grade, i.e. has "junk" status). (Source: Standard & Poor's Business Risk / Financial Risk Matrix).
These discrete thresholds thus give companies incentives to be lie just below a threshold. They can achieve this by short-term behavior such as cutting research and development (R&D). This increases EBITDA, thus reducing the Debt/EBITDA ratio and potentially meeting the threshold. Importantly, the incentives to engage in short-termism depend on where the firm is compared to the next lowest threshold. A firm with a Debt/EBITDA ratio of 2.1 has strong incentives to engage in short-termism, because it has a high chance of being able to lower it to below 2.0, but a firm with a Debt/EBITDA ratio of 2.5 has much weaker incentives. Taylor indeed finds that firms close to a threshold are significantly more likely to cut not only R&D, but also selling, general, and administrative (SG&A) expenses, which contains expenditure in advertising, information technology, employee training, and other forms of organizational capital.
Other papers have previously found evidence of short-termism to meet other types of thresholds - for example, companies may cut R&D to ensure their earnings fall just above analyst earnings expectations. But a particularly novel finding of this paper is that Taylor is able to document negative long-run effects of such short-termism. Companies close to ratings thresholds subsequently suffer declines in the number of patents that they produce, and also the number of citations to their patents (a measure of the quality of innovation). They also experience declines in profitability and valuation ratios.
The cost of credit ratings that critics typically focus upon is that inaccurate ratings lead to redistributional consequences. If the ratings of a security are too high, the buyer pays too much for them. Thus, the seller wins and the buyer loses. While these redistributional concerns are clearly very important, they don't directly affect the overall size of the pie (sellers get a larger slice, buyers a smaller slice). In contrast, Taylor shows that credit ratings have efficiency (rather than just redistributional) consequences - they affect the overall size of the pie. If companies cut investment to meet ratings thresholds, they erode their future value, making everyone worse off in the long-run. This is a particular concern for the 21st century firm, whose value is especially driven by intangible assets (such as brand strength, innovative capabilities, and corporate culture) which requires several years to build and bear fruit.
The paper certainly does not argue that credit ratings should be scrapped; these costs must be weighed against their numerous benefits. Many financial targets (e.g. analyst earnings expectations) also have the potential to lead to short-termism. Rather, the paper highlights a potential cost to credit ratings that boards may be able to mitigate. One potential remedy that discussed in a previous post is to increase the vesting period of executives' stock and options, to tie them to the long-run performance of the firm.