IELTS Writing Task 1: pie chart without numbers

Somebody asked me: What should I do if the question contains a pie chart without numbers on it? Well, let's look at a simple example.

The chart below shows the proportions of adults in Canada who own one car, two cars, more than two cars, or who do not own a car.

Would it still be possible to describe the pie chart above, even though the figures are missing? (Note: this is just a quick example, not a real question)