Under my idea, the demand for it would decrease which drives up the price.

If the demand decreases, and the supply remains the same, there will be a surplus.

With the passage of time, the demand of animals is decreasing.

With the increase in popularity of digital photography, the demand for film development has decreased.

Towards the end of the 1990s, the demand in Japan decreased due to the long economic crisis.

As demand for commodities decreased, so did their prices.

However, as economic growth and average income improved, the demand for whale decreased.

If the demand decreases, then the opposite happens: a shift of the curve to the left.

As far as we can see, demand is not decreasing at the moment.

Similarly, if the demand decreases, I will release officers back to other duties.