Ever since the 1980s I have been researching vaccine data, but I cannot seem to figure out – for the life of me – how many actual adverse reactions experienced by vaccinees are reported to VAERS, since there are so many data variables, plus estimated figures bandied around, as you will soon learn.
The vaccine adverse reactions reporting conundrum apparently gained some legitimacy with this report:
VAERS MAY ACCOUNT FOR ONLY 1 PERCENT OF ACTUAL VACCINE INJURIES [Nov 2, 2015]
But how many children have vaccine reactions every year? Is it really only one in 110,000 or one in a million who are left permanently disabled after vaccination? Former FDA Commissioner David Kessler  observed in 1993 that less than 1 percent of doctors report adverse events following prescription drug use. There have been estimates that perhaps less than 5 or 10 percent of doctors report hospitalizations, injuries, deaths, or other serious health problems following vaccination. The 1986 Vaccine Injury Act contained no legal sanctions for not reporting; doctors can refuse to report and suffer no consequences.
Even so, each year about 12,000 reports are made to the Vaccine Adverse Event Reporting System; parents as well as doctors can make those reports. However, if that number represents only 10 percent of what is actually occurring, then the actual number may be 120,000 vaccine-adverse events. If doctors report vaccine reactions as infrequently as Dr. Kessler said they report prescription-drug reactions, and the number 12,000 is only 1 percent of the actual total, then the real number may be 1.2 million vaccine-adverse events annually.  [CJF emphasis]
— Barbara Loe Fisher, Co-founder & President National Vaccine Information Center (NVIC)
Now here’s where things can get somewhat “squirrelly,” I think. In checking CDC/FDA and the feds websites, I find varying explanations and numbers for estimated yearly VAERS reports.
Since 1990, VAERS has received over 123,000 reports as of June 14, 2014
[VAERS-1 Form used from 1990 to June 30, 2017]
In recent years VAERS has received approximately 40,000 U.S.