The given chart illustrates the changes in car ownership among households in a European country over the course of 30 years, from 1971 to 2001.
Overall, it can be seen that car ownership witnessed an upward trend over 30 years, with the percentage of households without a vehicle decreased considerably, while the proportions of households in possession of one or two cars both experienced significant increases. By the end of the tracking period (giai đoạn theo dõi), households that own a single car became the most prevalent among others.
At the beginning of the period, approximately 50% of households did not own a car, while around 36% owned one, making it the second most common category. Households with two cars were in the minority, under 20%. This distribution shows that not owning a vehicle was the norm in 1971, with nearly half of the households falling into this category.
For the following 30 years, the figure for careless households registered a dramatic increase, ending at about 32% in 2001. Conversely, single-car households increased appreciably, peaking at 50% in 1991 before falling in 2001, with roughly 42%. In addition, dual-car ownership saw a sharp increase in 1981, with nearly 24%, but this possession of two cars fell slightly in 1991, with the figure being over 20%. However, this category rose again in the following 10 years, with more than 33%.