The graph illustrates the average monthly charges (in euros) for four different mobile phone companies from January to September 2002.
It is evident that Sim TX experienced the fastest rise in service fees, despite Domo generally having the highest prices. Lex saw a slight increase in charges, while Alpha’s service costs remained mostly stable.
Domo had the highest monthly contract fees, ranging from 15 to 25 euros, with the peak occurring in July. Conversely, Sim TX offered the lowest service cost for the first six months at approximately 5 euros. It matched Alpha at 10 euros in July and surpassed Domo in September, reaching 25 euros, which was a fivefold increase from its initial fee.
Like Domo and Sim TX, Lex’s charges also increased over time, but the rise was relatively modest (7 euros) compared to the other companies. In contrast, Alpha’s costs remained quite stable, with a minor increase of 4 euros between May and June, before reverting to its usual level of around 10 euros per month.
