Growth and progress have become so commonplace in recent times that various language devices are being used to give these concepts extra intensity. To indicate really significant progress, for example, we now say that a "breakthrough" has occurred. And to express the idea of sizable increases, we resort to the word "explosion," as in population explosion, cultural explosion, wage explosion, and suburban explosion.
The growth of air transportation in the last several years is among such detonations. Since 1962, the average annual growth rate of the US scheduled airlines has been about 16%, which is considerably higher than for any other major industry. And the outlook for further increases is very favorable. The Air Transport Association predicts that by 1975 the nation's airlines of all types, including international carriers, will fly 336 million passengers yearly, as compared with 97 million in 1965.
Last year United Air Lines carried 18,040,000 passengers,
Kidera GJ. Clinical Aspects of Commercial Aviation Medicine. JAMA. 1967;201(4):242-246. doi:10.1001/jama.1967.03130040038010