The line graph compares the single fridge production duration for three manufacturers in years of 1990 and 2000.
Overall, the production time of a refrigerator in all three companies saw a decreasing trend generally from 1990 to 2000, whereas the duration changing for company B was relatively low within three companies.
In 1990, the company C spent the longest time to make a refrigerator, which was 35 hours to produce a refrigerator. However, the company A and the company B spent much lower time to manufacture one refrigerator compared with the company A, within 30 hours and approximately 27 hours respctively.
While the time turned to 2000, the manufacture time for one refrigerator in both the company A and the company C reduced dramaticlly.
