Ken Doctor saw it coming. A few years ago, the media analyst looked at the trend lines and predicted that by 2017 or so, American newsrooms would reach a shocking point.

“The halving of America’s daily newsrooms,” he called what he was seeing.

Last week, we found out that it’s true. A Pew Research study showed that between 2008 and last year, employment in newspaper newsrooms declined by an astonishing 45 percent. (And papers were already well down from their newsroom peak in the early 1990s, when their revenue lifeblood — print advertising — was still pumping strong.)

The dire numbers play out in ugly ways: Public officials aren’t held accountable, town budgets go unscrutinized, experienced journalists are working at Walmart, or not at all, instead of plying their much-needed trade in their communities.

One problem with losing local coverage is that we never know what we don’t know. Corruption can flourish, taxes can rise, public officials can indulge their worst impulses.