A leading shampoo brand has lost five points of market share in two years. What would you look at?

Can I check how share is measured? Is it share of value or of bottles sold, and across which channels? I'd look at it in three layers, from the outside in. The first is whether the category is shifting under them. So I'd split the category by segment, meaning mass, premium and salon, and by need, like dandruff or color care. Then by channel, meaning supermarkets, drugstores, discounters and online. The second is whether they're losing inside their own segments. I'd check three things. Price is one. Has the gap to the nearest rival and to store brands widened? Distribution is another. Are they in fewer stores, or have they lost shelf space or promotion slots? The third is the product and brand. Are fewer households buying it, or are the same households buying less often? The last layer is who took the share. I'd want to see if it was one big rival, store brands, or a lot of small new brands. That should show where the five points went. I'd start with share by segment and channel.

Can I check how share is measured? Is it share of value or of bottles sold, and across which channels? I'll assume it's value share across all channels, down from 25% to 20%. I'd look at it in three layers, from the outside in. The first is whether the category is shifting under them. Share can fall with nothing wrong in the brand if the growth is in parts of the category it doesn't sell in. So I'd split the category by segment, meaning mass, premium and salon, and by need, like dandruff or color care. Then by channel, meaning supermarkets, drugstores, discounters and online. If the growth is in premium products sold online and this is a mass brand in supermarkets, the five points are a gap in the range. The second is whether they're losing inside their own segments. I'd check three things. Price is one. Has the gap to the nearest rival and to store brands widened? Distribution is another. Are they in fewer stores, or have they lost shelf space or promotion slots? The third is the product and brand. Are fewer households buying it, or are the same households buying less often? Losing buyers, with distribution unchanged, points to the brand's appeal. Buying less often points to promotions, or to people adding a second brand. The last layer is who took the share. I'd want to see if it was one big rival, store brands, or a lot of small new brands. Those call for different responses. You can answer one rival's price cut. A dozen small brands growing at once means shoppers want something this brand doesn't offer. My hypothesis is that it's mostly the first layer, with small premium brands growing online and in drugstores. That's my guess, and the split will test it. I'd start with share by segment and channel for the last three years. Is that available?