If you live in the U.S or the UK, you've never been safer. Despite grim economic times, you are less likely to be murdered, raped or have physical violence inflicted upon you than at any point in the last 20 years.

According to the latest figures released Thursday, the murder rate in the UK fell by 14 percent year-on-year to 550 homicides in 2011-12; the lowest it's been since 1983. Violent crime in England and Wales also fell by 7 percent, while robberies declined by 2 percent.

It's a similar picture across the pond. In June, the FBI recorded a 4 percent drop in violent crime, the fifth straight year it has fallen. Property crimes -- which according to the FBI include thefts, burglary, car crime and larceny -- also dropped by 0.8 percent.

In the UK, the continued drop found in the Crime Survey for England and Wales figures has confounded critics of the Cameron government, who predicted a 20 percent cut to police budgets and a persistent recession would lead to an uptick in crime and anti-social behavior.

Baffled criminologists have offered a range of ever more bizarre and outlandish reasons to explain the trend decline in the U.S., including the removal of lead from paint and petrol, the legalization of abortion following Roe Vs. Wade and even positing that crack babies born to drug-addled mothers at the height of the crack cocaine epidemic in the 80s and 90s turned out to be not as physically damaged as first thought.

But while these explanations do go some way to explaining the decline, they also allude to another more worrying point; nobody really knows why this is happening.

This is surprising, especially given the economic crisis and rising unemployment, said Rick Muir, Associate Director for public service reform at British think tank the Institute for Public Policy Research.

Previously when this [economic conditions] happened in the 70s and 80s we didn't see the same fall in crime.

I haven't seen any proper analysis on why this is the case.

After all the academic papers, statistics and political hot air expended on the latest crime fighting initiatives, we are no closer to pinning down exactly why crime rates have fallen.

But despite the lack of a smoking gun, Muir does think that, for the UK at least, there are some macro trends that may help explain the stats.

The police are much better equipped to deal with crime... their ability to analyze and prevent crime has also increased, they are quite sophisticated in deploying assets now.

It's certainly true to say that over the last few years we have seen a lot of investment in the public infrastructure in the UK and an investment in policing.

Secondly, Muir added, the UK is a much more socially cohesive than in previous generations.

We have something of a healing of the scars of the big wave of de-industrialization in the UK, he said.

Even though we currently have an economic crisis, there is resilience in our public services and the strength of our communities to better resist it.

Relative economic prosperity, technological innovation and a more globalized economy may also have played their parts.

The plummeting value of household goods such as DVD players, televisions and computers has certainly reduced the financial incentive to commit burglary, while the advent of tracking devices, immobilizers and more advanced car alarms has made it more difficult to commit vehicle crime.

The fact that most people now carry around one of the most expensive items they own in their pockets, their mobile phone, could also be one possible reason for the 2 percent rise in pickpocketing noted in the UK figures.

And ultimately, given the massive social upheaval of the 70s and 80s, the 90s and 2000s have been -- give or take an economic collapse or two -- relatively stable.

The problem, Muir concludes, is that the crime debate tends to take place in the absence of any serious academic work into what is really going on.

It is disappointing and surprising. No one has a really well evidenced answer as to why it is the way it is.

But before we all celebrate too soon, a note of caution.

Crime rates in both countries fell dramatically during the 90s and early 2000s. In recent years, however, this trend has decelerated, with rates in the UK holding steady for the past three years.

Today's figures show that crime levels have remained unchanged in the last year, as has been in the case in the two previous years, said Jon Collins, Deputy Director of the Police Foundation.

This suggests that the long downward trend in crime, and particularly in vehicle crime and burglary, since the mid-1990s has come to an end.

After all, we are only a couple of years into the current economic malaise. If unemployment -- particularly among the young -- continues the way it has, then crime levels could begin to rise once more.

It is important to remember that it may be some time before the full effects of the current economic situation are felt, Collins concluded.