Today Boeing (NYSE:BA) released its forecast for the demand for all aircraft in the industry over the next 20 years and noted it expects 36,770 new airplanes to be needed across the globe between 2014 and 2033, with a total value of $5.2 trillion.

This forecast represents an increase of 1,500 planes (4.2%) over Boeing's projections from last year. At that time it projected the total demand from 2013-2032 to be nearly 35,280 plans with a value of $4.8 trillion. 

"This market is strong and resilient," said Randy Tinseth, vice president of Marketing, Boeing Commercial Airplanes, in a press release. "With new and more efficient airplanes entering service, the growth in air travel is being driven by customers who want to fly where they want, when they want."

Boeing expects the biggest demand over the next 20 years to be for single-aisle aircraft, with the total number of single-aisle airplanes in service projected to more than double, growing from 13,580 in 2013 to 29,500 in 2033. Boeing expects nearly 70% of the demand from 2014 to 2033 -- or 25,680 new planes -- to be in the form of single-aisle aircraft.

Boeing said the reason behind this growing demand would be from "fast-growing low-cost carriers and network carriers pressed to replace aging airplanes."

As shown in the charts below, single-aisle aircraft represent the greatest segment of the market in terms of both total planes and dollar value of new orders:

Source: Boeing Current Market Outlook.

Boeing expects the biggest driver of growth will be the Asia-Pacific region, claiming roughly 40% of the total plane deliveries and the total market value:

Source: Boeing Current Market Outlook.

The company projects 15,500, or 42%, of the new deliveries will replace airplanes which are older and less efficient. The remaining 21,270, "will be for fleet growth, which stimulates expansion in emerging markets and development of innovative airline business models." In total, Boeing believes the global fleet of airplanes will grow to 42,180 by 2033.