MATHEMATICS professor John Allen Paulos once said that "uncertainty is the only certainty there is, and knowing how to live with insecurity is the only security".

These are wise words on how to live your life, to be sure, but they are also notably apposite to the economic situation that Singapore faces today.

With the world in the grips of the worst recession in decades, no one really knows how badly the economy is going to do this year.

Since the Ministry of Trade and Industry (MTI) first started predicting this year’s growth figure in November last year, it has already lowered its forecast twice.

On Thursday, Prime Minister Lee Hsien Loong said a third revision is on the cards next Tuesday, when MTI releases its preliminary growth data for the first quarter of this year.

The current official forecast is for Singapore's economy to shrink by between 2 and 5 per cent this year. Private sector economists are largely clustered around the worse end of that spectrum, with most predicting a contraction along the lines of 5 per cent or more.

One research house has even come out to predict a dramatic 10 per cent decline in growth this year, but PM Lee said that a double-digit contraction is unlikely.

All this number talk is well and good, but if you're a normal human being who doesn't care so much for the dismal science, you're probably wondering what all this means.

To me, there are two takeaways here. First, changing the growth forecast three times in less than five months reflects the highly uncertain and volatile times we are living in right now.

Even up to last November, the Government thought there was a good chance the economy would grow this year.

Now, not only has any chance of growth completely disappeared, but the predictions of decline have become so dire that coming up with a number has almost lost all meaning.

Consider this: any contraction beyond 4 per cent is already unprecedented in Singapore's history, so a 10 per cent contraction is pretty much unimaginable.

Still, the numbers are not wholly unimportant, which brings me to my second point.

Many economists think that the economy has already shrunk by 8 to 10 per cent in the first quarter this year, over the same time last year.

Putting this together with PM Lee's indication that this year's contraction will be in the single digits, what this essentially means is that the most severe decline in the economy must have been in the first quarter, which ended last month.

Subsequently, the economy is going to continue shrinking, but at a slower pace.

And depending on what forecast the Government comes up with next Tuesday, it will give us an idea of whether the economy is expected to shrink throughout the whole year, or start to recover in the second half.

So the numbers themselves may not make any sense – and changing the official forecast several times may make you wonder why we have a forecast at all – but in this new era of uncertainty, any additional information helps.