The provided graph illustrates the variation in the number of enquiries received by the Tourist Information Office in one city over a six-month period in 2011.
Overall, the graph indicates that the volume of in-person enquiries and enquiries received by telephone showed a consistent upward trend throughout the period, while the number of enquiries via letter/email declined notably from March to June.
The data reveals a substantial surge in in-person and letter/email enquiries from January to April, with an increment of approximately 500 inquiries recorded by April compared to January. In contrast, telephone enquiries remained relatively stable during this period, only experiencing a slight drop from 900 in January to 800 in February. From April to June, both in-person and telephone enquiries witnessed a significant increase, reaching around 2000 and 1600 inquiries respectively by June.
In contrast, the trend for letter/email enquiries followed a different pattern. These enquiries maintained stability at around 800 from January to April before experiencing a sharp decline to below 400 by June. This decline was drastic, halving the number of enquiries within the span of just two months.