Data analysis and interpretation tricks-bar-chart diagrams

Data analysis and interpretation problems are given to test how keenly you can observe things and not to test your ability to calculate.Let us now see some data analysis and interpretation tricks to get the answer quickly without much calculations.

Study the following graph carefully and answer the questions   below.

(1)In which year the percentage increase or decrease in the production of company B to that of company A was maximum?

Basic concept
First of all we shall look at each bar as group of parts and understand the concept of parts.

for example In the above bar chart diagram, In 2007 company A has 1 part and company B has 2 parts
In 2008 company A has 3 parts and company B has 4 parts.

Steps to find percentage increase or decrease

We  shall follow the below steps to arrive at our answer
Step 1:Count the number of parts of company A and company B
Step 2:Compare the number of parts of company B with company A for all years.
Step 3:Check which year the difference in the number of parts is maximum.That is the year the percentage increase or decrease is maximum