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Identify 2 significant point of comparison...

Extract A compares the price indexes of new and used cars using 2005 as the base 100. It is visible that the price of used cars fluctuates much more than the price of new cars. The range of prices of used cars is around 55 whereas the new cars only fluctuate around 10.

Comment:
Use units
Not the price but the price index fluctuates

New car prices went down to a trough of 95 in 2002 and a peak of 106 in 2008. Used cars reached their peak at the beginning of 1998 or around 132 to an all time low of 80 in 2008. This shows that the trend for new cars is that the prices are increasing slowly but steadily whereas used car prices are massively dropping at a rate of 5 index points a year since 1998.

Comments:
Price index went to 95 not the prices*
Use units

Ideally:

The price of new cars rose over the whole period from an index of approximately 100 in January 1996 to an index of approximately 105 late in 2008 whereas the price of used cars fell from an index of approximately 125 to an index of approximately 82 late in 2008.

After 2005 there were fluctuations in the price of used cars but not in the price of new cars e.g. in 2001 the price index for used cars fluctuated between a high of aprox. 118 and a low of aprox. 113 whereas the price index for new cars was stable at an index of aprox. 95