The graph details the amount of hour used on manufacturing one automobile by Audi, Mercedes, Volvo and Nissan from 1999 to 2006. Overall, while statistics of other three companies had different rates, Volvo remained stable.
In terms of Audi, the duration of producing vehicle began with about 32 hours, which was an all-time high rate and gradually declined until the 2003, with 24 hours. However, the change became slight in three years, only two hours. Volvo started with 23 hours, that witnessed no fluctuation and stood stable.
Turning to Mercedes, spent time was 25 hours in 1999. After being constant for 2 years, it reached their highest figure, with 27 hours. It ended up with 24 hours in 2006. Nissan saw a huge fluctuation during eight years. When Nissan began just above 20 hours, it reduced to 20, then rised to 23 hours continuously. This company spent only 23 hours in 2006, as Volvo did.
