jumped by 3% to 12% over this 10-year period
The source of the data for these claims and Figure 1 is "JobsEQ": https://www.chmura.com/software. The figure shows an annual average growth rate of technology firms of 5% (compounding to 60% over ten years). The scaling of the axis makes it look more dramatic. I originally thought that this was "not impossible" (though obviously very suspicious) based on state-level growth rates for venture-backed startups. However, the 'Relative Growth' analysis below clarifies that this is well outside the bounds of possibility at the state level for the technology sector as a whole for any prolonged period. It also confirms the stylized fact that the number of technology firms declined for the US as a whole over this period.
The Business Dynamics Statistics data from the U.S. Census is the standard data source for entry and exit and is available at the state-NAICS2 level from 1978 to 2019 (an update is due). There are numerous well-documented issues with using BDS, including that it measures establishments, not firms, and that the Census restricts access to sparse data. See the [[American Community Survey (ACS) Data]] page for related information.