The line chart depicts the difference of the average cost of monthly contract for types of mobiles (Domo, Lex, Sim TX, Alpha) in a European country from January to September 2002.
Overall, it is obvious that the price of cell phones experienced upward trends during the 9 months starting from January, except Sim TX. Meanwhile, Alpha had a significant frustration among all four mobiles.
In the first month of the year, Domo was an expensive mobile contract at 15 euro, followed by Lex with a lower cost at around 12 euro, Sim TX at 9 euro and Alpha at 5 euro. From January to July, there was a considerable growth of 25 euro in Domo and suddenly decreased slightly to 3 euro in September.
In contrast, Lex’s cost declined slowly from 12 euro to 10 euro before covering to 17 euro between January and September. However, the price of Sim TX had a modest increase of 18 euro, and then plummeted sharply to 8 euro. At the same time, Alpha remained steady over a 6-month period, afterward it witnessed a dramatic plunge and surpassed the cost of Domo, reaching a peak of 25 euro. Alpha became the most expensive mobile plan in September .