The pie charts compare the time given on different activities of an American office in the years of 1980 and 2000.
Overall, it is clear that majority of office time was given on phones and least on computers in 1980, but it changed within next 20 years while majority of time was spent on computers and least on emails. Activities like using phone, paper documents and meetings demanded more time in 1980 than is required in 2000.
In 1980, time given on phone, paper documents and meetings were around one third(30%), two tenths and 19% respectively which dramatically declined within next 20 years and needed only half of the time that required in the previous. On the other hand, time spent on face-to-face communications and other activities were 14% and 15% respectively, which remained stable over the 20 years time period.
However, in case of computer works, it was only 2% of given time at a office in 1980, which sharple increased to approximately a third(30%) in 2000. Surpriseingly, there were no email related works back in 1980, whereas it demanded 8% of whole office hours in 2000.