The line graph illustrates the standard time for producing motor vehicles of four corporations in the US from 1998 to 2005.
It is notable that all of those manufacturers made considerable achievements in reducing lead time. Additionally, Honda predominated with the shortest manufacturing time for most of the period.
In 1998, General Motor allocated the greatest amount of time to produce cars, typically 32 hours, approximately 1.2 times the figure for Ford. Meanwhile, Toyota vehicles were produced in only 22 hours and showed no disparity compared to Honda.
During the first four years, the proportion of automotive companies below followed various patterns. Particularly, General Motor shortened production time to nearly 27 hours, down roughly 15%. The figure for this company was surpassed by that of Ford when Ford experienced a significant increase to reach a peak of 31 hours in 2001. On the contrary, the average hours of two Asian manufacturers fluctuated between 20 and 23 hours and attained about 22 hours in 2001, remaining relatively unchanged compared to 1998.
From the year 2001 onwards, the production time of Toyota and Honda rose by 2 hours in 2002, followed by a considerable drop to just over 20 hours in 2012. On the other hand, the lead time of General Motor fell to 24 hours, while the figure for Ford decreased by 25% and hit a low point at below 24 hours in the last year.