Family Radio evangelist Harold Camping in an interview in April. (Screengrab from )

Since we’re all still here, it seems those dates weren’t exactly accurate, but that hasn’t stopped doomsayers from continuing to predict the Rapture — even if they were wrong the first time around.

The latest comes courtesy of Family Radio evangelist Harold Camping, 89, who has proclaimed May 21 to be the day when Jesus will come down to Earth and prepare for the End Time. He and his followers have splashed the news on billboards around the country. It’s not the first time Camping’s been predicting the end of days.

He predicted the Rapture would arrive in September 1994.

What happens when you expect the world to end and you still wake up the following morning?

It’s all about allowing for a margin of error in the predictions.

Camping explained how his earlier prophecy went wrong to the Washington Post’s Michael Rosenwald:

It’s just like anyone who invents something or comes to a truth or any technician — they don’t immediately make a finished product....I did not come to the finished product until three years ago. It was at that time that God showed some exquisite proof.

Camping is not alone in reconsidering his predictions.

Former NASA Engineer Edgar Whisenant also wrote a book predicting the rapture, called 88 Reasons Why the Rapture Could be in 1988.

In the Washington Post’s On Faith section, blogger Jason Boyett talks about how his childhood church grabbed on to Whisenant’s prediction.

When Whisenant was wrong, he revised his date multiple times. When none of those dates turned out to be correct, he claimed he had made a slight miscalculation of one year because of a fluke in the Gregorian calendar. Whisenant continued to revise his date annually until he died in 2001.

One of the most famous early prophesies was by Baptist Minister William Miller, who predicted Jesus Christ would return in 1844. When Jesus didn’t come, the year was dubbed “The Great Disappointment.”

Miller was ridiculed by the public for his mistake. Miller wrote to a friend:

Some are tauntingly enquiring, “Have you not gone up?” Even little children in the streets are shouting continually to passersby, “Have you a ticket to go up?” The public prints, of the most fashionable and popular kind …are caricaturing in the most shameful manner of the “white robes of the saints...”

Miller kept predicting end dates until his death five years later.

Jehovah's Witnesses first anticipated the end of times in 1914, now noting on their official Web site “not all that was expected to happen in 1914 did happen, but it did mark the end of the Gentile Times and was a year of special significance.”

Pastor John Hinkle of Christ Church Los Angeles predicted that on June 9, 1994, God would “rip the evil out of the world.” Hinkle insists the event happened, but people may not have noticed it.

In 2000, the Y2K computer problem combined with the prophetic sound of the year led to predictions of comets, tidal waves, alien invasions and computer crashes, none of which occurred.

The list of doomsayers goes on. Some sites list dozens upon dozens of end of the world predictions.

As for Harold Camping, he has not allowed past mistaken prophesies to dissuade him. Watch an interview with Camping conducted by Stephen Meyers, president of the Institute for Biblical and Scientific Studies. Camping explains his beliefs:

If the Rapture doesn’t come next week, on May 22, 2011, Camping will likely explain he has more research to do.