An angel investor is an individual who provides capital to a business or businesses, including startups, usually in exchange for convertible debt or ownership equity. Angel investors often provide support to startups at a very early stage , once or in a consecutive manner, and when most investors are not prepared to back them. In a survey of 150 founders conducted by Wilbur Labs, about 70% of entrepreneurs will face potential business failure, and nearly 66% will face this potential failure within 25 months of launching their company. A small but increasing number of angel investors invest online through equity crowdfunding or organize themselves into angel groups or angel networks to share investment capital and provide advice to their portfolio companies. The number of angel investors has greatly increased since the mid-20th century.