Using the Internet as a Data Source
The classic Excel application has two sources of data—databases on the network, and the user. If an
item of data was not available in a database, the user was required to type it in and maintain it. To
enable this, the application had to include a number of sheets and dialogs to store the information and
provide a mechanism for the data entry.
A typical example of this would be maintaining exchange rate information in a financial model; it is usually
the user’s responsibility to obtain the latest rates and type them into the model. You can add value
to the application by automating the retrieval of up-to-date exchange rate information from one of many
web sites.
The following sections demonstrate different techniques for retrieving information from the web, using
the USD exchange rates available from www.x-rates.com/d/USD/table.html (see Figure 24-1) as an
example.