The given two line charts illustrate the percentage changes of the ownerships of three particular electric devices that are used in households and number of hours spent doing household works in a country from 1920 to 2019.
Overall, from 1920 to 2019, as the ownership of electrical appliances such as washing machine, vacuum cleaner and refrigerator increased, the number of working hours spent on household works at home decreased.
The primary inference that can be drawn is that the ownership of refrigerator and vacuum cleaner steadily increased from 1920 to 1980 and 2000 respectively to reach the highest percentage. In 1920, the percentages of refrigerator and vacuum cleaner were between 0 to 10 and around 30 respectively. These percentages reached the fullest, which is 100 in 1980 for refrigerator and 2000 for vacuum cleaner and continued until 2019.
Secondly, washing machine ownership rose from 1920 to 1960, then it experienced a slight decrease in proportion and again started to increase until 2019. The percentage of washing machine in 1920 was approximately 40, in 1980 it was between 60 and 70 which then rose to just above 70 in 2019.
Last but not least, housework hours per week gradually decreased from 1920 to 2019. The number of hours of housework for an individual home in 1920 were nearly 50 hours per week. These hours steadily decreased to around 10 hours per week in 2019.