The given line graph compares how many investigations were surveyed by the Tourist Information Office in a city in the period from January to June in 2011. Overall, it can be seen that the enquires received by the telephone and in person went up while those by letter or email went down in this period.
In January, while the number of investigations surveyed in person were the lowest figure, at nearly 400, those by telephone and letter or email were higher, at about 900 and 750, respectively. In March, the number of investigations in person doubled those in the two previous months and became the second highest figure. On the contrary, the number of enquires received by letter or email decreased lightly to about 700 and became the lowest figure. This period saw a fluctuation in the number of enquires surveyed by telephone and reached 1000.
The period from March to June experienced a significant increase in the number of investigations received by telephone to 1600. Another significant characteristic is that the figure in person increased dramatically and became the highest, at 1900. Meanwhile, there was a rapid decline in the number of enquires received by letter or email to below 400.