… 101 vehicles that are or have been under development in the last four years. “Let that sink in for a little bit,” [Carlos Niederstrasser of Northrop Grumman] said. “One hundred and one different entities are trying to build a small rocket to get all your small satellites into space. The number is staggering.”

Of those 101 vehicles, he says that six are now operational, 34 are still in development, 11 have gone defunct, and he is unsure of the current status of another 11.

The amazing growth in small launch vehicle development as well as the growth in satellite projects shows the difference that has happened in a decade, now that NASA, NOAA, and the U.S. military have shown an interest in using commercial services. A decade ago, investors were reluctant to get into space projects other than communication satellites, but now they are eager to invest in them.

Col Beausabre: I agree that in the early days NASA hired contractors to build their suborbital sounding rockets, but over time the ownership and control and design of those rockets was taken over completely by NASA. What we are seeing today is a transfer of the owner, control, and design back to the private sector.

I suppose that it depends on your definition of “suborbital” but many of NASA’s sounding rockets, such as Aerobee (over 1000 launches) were designed and built by private contractors.

https://en.wikipedia.org/wiki/List_of_sounding_rockets

If you want the details on almost any bird ever flown this is available as a free PDF on line, International missile and spacecraft guide Ordway, Frederick I., III (Frederick Ira), 1927-2014.

https://babel.hathitrust.org/cgi/pt?id=mdp.39015011128397;view=1up;seq=2

This is good too, Encyclopedia Astromanutica

http://astronautix.com/