first few years of the company. While their 1980 games were modest hits, one of the company's first successful games was Kaboom!, released in 1981, which was Activision's first game to sell over a million units. Activision's breakout title was 1982's Pitfall!, created by Crane. More than four million copies of the game were sold. Near the end of 1982, Kaplan left Activision to work on the development of the Amiga personal computer as he wanted to be more involved in hardware development. Total sales for Activision were estimated at and revenues at ahead of its June 1983 initial public offering; at this point Activision had around 60 employees. Danny Goodman stated in Creative Computing Video & Arcade Games in 1983, "I doubt that there is an active [Atari 2600] owner who doesn't have at least one Activision cartridge in his library". The company completed its public offering in June 1983 on NASDAQ under the stock ticker AVSN. The video game market crash (1983–1988) The success of Activision, alongside the popularity of the Atari 2600, led to many more home consoles third-party developers as well as other home consoles. Activision produced some of its Atari games for the Intellivision and ColecoVision consoles, among other platforms. However, several new third-party developers also arose, attempting to follow the approach Activision had used but without the experience they had; according to Crane, several of these companies were founded with venture capital and hired programmers with little game design experience off the street, mass-publishing whatever product the developers had made. This was a contributing factor to the video game crash of 1983. For Activision, while they survived the crash, they felt its effects in the following years. These third-party developers folded, leaving warehouses full of unsold games, which savvy retailers purchased and sold at a mass discount ( compared to Activision's manufacturer's suggested retail price). While there was still a demand for Activision games, uneducated consumers were more drawn to the heavily discounted titles instead, reducing their income. Their quarterly revenue dropped from in mid-1983 to about by the end of 1984, according to Levy, and were forced to lay off staff, going from about 400 employees to 95 in that period. Because of this, Activision decided that they needed to diversify their games onto home computers such as the Commodore 64, Apple, and Atari 8-bit family to avoid completely going out of business