Overall, all manufacturers produced cars more quickly over the period, with General Motors showing the most notable improvement in its production time. In addition, Honda had the fastest production lines for most of the period.

(Body 1: GM and Ford)

Regarding the two American manufacturers, in 1998, it took GM 32 hours to produce a car, about 4 hours more than Ford. The former company then saw a steady decline in its production time, ultimately falling to 22 hours over the period. Meanwhile, the number of hours to make Fords peaked at 31 hours in 2001, before falling by a third to only 21 hours at the end of the timeframe.

(Body 2: Toyota and Honda) 

As for the remaining companies, in 1998, both Toyota and Honda required approximately 22 hours per vehicle. Thereafter, Toyota's production time showed fluctuations between 22 and 24 hours, followed by a significant decrease in the last 2 years, ending up at just 20 hours in 2005. Likewise, despite a drop of 2 hours in 1999, Honda's production slowed to reach a high of 24 hours per car in 2002, before falling back to 20 hours over the final three years.

Overall, it is clear that there were significant changes in the amounts of waste produced by all three companies shown on the graph. While companies A and B saw waste output fall over the 15-year period, the amount of waste produced by company C increased considerably.

(Body 1: from 2000 to 2005)

In 2000, company A produced 12 tonnes of waste, 4 tonnes more than company B and three times the waste produced by company C. Over the following 5 years, the waste output of companies B and C rose by around 2 tonnes, but the figure for company A fell by approximately 1 tonne.

(Body 2: from 2005 to 2015)

From 2005 to 2015, company A cut waste production by roughly 3 tonnes, and company B reduced its waste by around 7 tonnes. By contrast, company C saw an increase in waste production of approximately 4 tonnes over the same 10-year period. By 2015, company C􀀁s waste output had risen to 10 tonnes, while the respective amounts of waste from companies A and B had dropped to 8 tonnes and only 3 tonnes.

Overall, rivers in Northern Ireland and Wales consistently had the cleanest water. In addition, with the exception of Wales, all the regions showed improvements in their water quality over the period shown.

With regards to the two leading nations, in 1990, roughly 96% of rivers in Wales were classified as having good chemical levels, noticeably higher than Northern Ireland's 83%. In the following years, Wales's river cleanliness remained relatively stable until 1998, before declining sharply to around 80% by 2002. In contrast, Northern Ireland's river quality gradually improved, with its purity rising to nearly 100% in 2000, and then slightly falling to 96% by 2002, having surpassed Wales since 1999.

Regarding the remaining countries, in 1990, Scotland's rivers were of the lowest quality in terms of chemical composition, with only 20% of river water there up to par, less than half of England's 45%. Subsequently, the latter's purity rose sharply to a peak of 70% by 1996, and then dramatically fell back to a low of 30% in 1998, followed by a significant recovery to 50% by 2002. Similarly, the percentage of clean water in Scotland rose steadily, reaching 60% in 2000 before declining to 40% over the final two years.