How has limited overs cricket changed tests?

There has been a lot of talk over the last few days of how limited overs cricket has changed the character of cricket, this comes in light of Sachin Tendulkar becoming the first man to breach the 200 mark in a 50 over match.


Sachin Tendulkar's 200 - highlights

So how has the advent of the limited overs game impacted on test cricket?

I've looked at the last 110 years of test cricket and the fluctuations in the average run rate decade by decade, and whilst a compelling case is not necessarily revealed, it would seem that since limited overs cricket came in to play a more uniform trend has emerged.

In the 1900s the run rate was 2.82, and in the 1910s it was 3.10, a 10% increase in the scoring rate from one decade to the next. However in the 1920s it dipped by a sizeable 14% to 2.66, before clawing back 1% to 2.71 in the 1930s. The 1940s saw half as many tests as the 1930s, for very obvious reasons, and the run rate dipped again by 3.3% to 2.62. In the 1950s we see a marked dip, of 12.2% back down to 2.3 runs per over.

However, moving into the 1960s we see an 8% increase to 2.49 and thereafter it is an upward trend. In the 70s we jump another 8% to 2.69, 6.3% up in the 80s to 2.86 before, interestingly (honest), it flatlined in the 1990s and stayed at precisely 2.86. In the 2000s we see it move up again, by 12% to 3.2 and then in the nine tests so far this year we've seen an 8% jump to 3.45.

If I haven't sent you to sleep by now, I'm doing well. You could argue that limited overs cricket has changed nothing, because the rate in 1910 (3.1) is not as substantially different as you might expect to now (3.4). However its pretty clear that run rates have been on the up ever since limited overs cricket was introduced.

Ever since the first ODI was played in 1970, the run rate in test cricket has increased by about 35%, that's a pretty big difference. Interestingly if you look at the run rates for ODIs alone, they've increase by almost exactly the same amount, but I suspect some of this specific increase could be accounted for by the introduction of fielding restrictions and power plays.

I must say though I was expecting a more marked increase in run rates since ODIs were introduced from one decade to the next, and I can't account for the fact that players are only scoring a bit faster than they did in 1900, but an interesting exercise nonetheless!

Update: It occurs to me that its probably worth noting that the volume of ODIs in the 2000s was significantly higher than in the 1990s, and likewise from the 80s to the 90s. There were just under 1,000 ODIs in the 1990s, but 1,500 in the 2000s, so the maintenance of an increased run rate over 50% more matches makes it a bit more marked I suppose.