Simple way to display “years of service” in html/javascript

I am trying to display a number for years of service on a website. Essentially I thought I could put in a start date and current date to have an output of the years in between.

I can gt the current year using the following code but am unsure how to calculate the deference

document.write(2010) + (/d{4}/.exec(Date())[0])

Answer

Just subtract 2010 from the current year and concatenate the string:

document.write((/d{4}/.exec(Date())[0]) - 2010 + ' years of service')

Although an easier way to get the year is to use Date.getFullYear():

document.write(new Date().getFullYear() - 2010 + ' years of service')