I have a doubt about the use of the first diagram in this case. Combined with the information 'the sales are falling because more doctors are opening their own labs', how can we generate useful insight from this chart? I personally find it difficult for 2 reasons:
1. There is no comparative information between the past and the present, so we really cannot tell which doctors are opening their own laboratories. It would be more persuasive if we have information like e.g. the revenue contributed by doctors who send 10 patients jumped from 10% to 5%.
2. Even if we agree with the assumption that ' doctors who send more patients to the lab are more likely to open their own lab', how can we know that those who sent only 1 patient to the client's lab doesn't have their own lab so they only send 1 per day? In a word, the market overview in terms of the revenue contribution of the client cannot represent the entire market situation. there are som many uncertainties.
It would be great to know how you think of the diagram.