the charts show the changes in ownership of electical appliances and amount of time spent doing housework

The line charts illustrate the proportion of electrical appliances in a given country from 1920 to 2019 and the quantity of time of doing household chores each week during the same time. Omit, three appliances are becoming more and more popular, especially refrigerators and vacuum cleaners. As a result, the total time spends on housework has decreased for a hundred years. At the beginning point, the percentage of refrigerators was 0%. Yet, this figure has soared by 55% and 90% in 1940 and 1960, . In 1989, this number grew up to 100% and reached a period of stability after 1980. Vacuum cleaners start higher at 30%, and then rose by 20% every 20 years until 1960 when growth slows down and reached 100% by 1980. On the other hand, washing machines began at 40%, increase to 70% in 1960, then fell and recover to finish the period at above 70%. As can be seen from the second chart, the number of hours of household per week per house has a steady fall by 30 hours from 1920 to 1960. After that, the decline was more gradual, reaching above 10 hours in 2019.