Valentine's Day Special 2007

As a special Valentine's Day treat, the JC Economist pens new lyrics (inspired by the ST excerpt below) to a familiar old song:

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The JC Economist's Favourite Things
(Sung to the tune of My Favourite Things
from the musical The Sound of Music)

Valentine’s Day falls on February 14th
Prices of roses go up before 14th
I wonder why prices go up so much?
Oh tell me, oh tell me, oh tell me why ….

Demand shifts right
Excess demand
Prices are pushed up
That’s why my roses cost so ve--ry much
I have to save up
To buy!

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When do the prices of flowers start to go up? (Excerpt from ST, 8 Feb 2007)
Prices of roses usually start going up a week before Valentine’s Day. On the day itself, they can be double the usual price. Other popular flowers like tulips and lilies also see their prices jump by about 20 per cent.

Food for thought
1. Before Valentine's Day, why does demand for roses 'shift right'? Does supply of roses also shift? Why or why not?