It is very difficult to make assumptions regarding the data extracted from the wallets. Most of the individuals may be having more than one wallet (I myself have dozens of BTC wallets).
Somehow, I think that it is true because many of us will not just use one wallet only. I am sure that people will create more than one wallet. We will keep our bitcoin to many wallets, so we don't keep the bitcoin in one wallet. We don't know people who have 1 bitcoin in their wallet because it is difficult to get the real data about who has own 1 bitcoin. We need to count on the wallet on every exchange, and I am sure that the exchanges will have more than a thousand of the user who will have more than one wallet too.