Blade Runner

You have to love economists, if not The Economist. Who else would note Gilette's recent announcement of a five-blade razor and then try to determine if there is a Moore's Law for razor blades (with a chart!)? By their reckoning, we'll be shaving with 14 blades by 2100. Word of advice: invest in Band Aids. But itg's possible we'll all look like ZZ Top by then.

This relationship (see chart) suggests shavers are going to get more blades whether they need them or not. However, just like Moore's law—the observation that computer chips double in power every 18 months or so—it seems that technology as well as marketing determines the rate at which new blades are introduced.

It is simply not possible to add a new blade whenever the marketing department wants one. Every additional blade, explains Michele Szynal, a spokeswoman at Gillette, adds weight and size to a razor. Firms must therefore find ways of making both razor and blades lighter, which means thinner blades, more closely spaced, made of special materials, with new coatings.

So what does the future hold? With only five data-points, it is hard to be sure exactly which mathematical curve is being followed. If it is what is known as a power law, then the 14-bladed razor should arrive in 2100. The spate of recent innovation, however, suggests it may be a hyperbola. In that case, blade hyperdrive will be reached in the next few years and those who choose not to sport beards might be advised to start exercising their shaving arms now.