The line graph illustrates several questions collected by the Tourist Information Office in a City from January to June 2011.
In general, the information collected by in person and telephone rose during six-month period. In contrast, the information summarized by letter or email declined in first six months of 2011.
In January, the data got by telephone was the highest, about 900, and the data got in person and letter or email respectively was about 750 and 420. In February, the telephone and letter or email respectively dropped to 800 and 700 while in person inquiries rose up to 600.
In four months later, in person questions rose considerably to 1900 and was the highest factor. By letter or email continued to decrease to lower than 400 while telephone rose up to 1600.