# Visual stock level representation

I'm working on production line management software for a small factory that deals with various kinds of stock. Stock generally decreases one-by-one and I want to show these stock levels visually in an intuitive way.

Is there any previous work in this area, which does not take up much more space than a number, but makes it obvious how much stock remains? An additional bonus would be to represent high or low levels (which are stock-specific) in a variable way.

There are at most 10s of different stocks and their levels can be anything from -10 (due to bad things) and 2,000, but levels will usually be in the 0-500 range. It would be nice to stand on its own, but if it accompanied an exact integer that would be nice.

My first attempt is stacked columns of coloured pixels, where the colours represent different denominations, kind of like poker chips:

Stock A 12,423
Stock B 398

So, Stock A would read from left to right as 12,423:

``````  4*2500 + 4*500 + 3*100 + 4*25 + 4*5 + 3
= 10,000 + 2,000 + 300 + 100 + 20 + 3
= 12,423
``````
• Hello @pate, could you perhaps provide us with the research and designs that you came up with, together with an explanation of why it's not working for you? :-) Aug 23 '15 at 21:14
• @Xabre: I will update the question with my designs as they progress, but I haven't done much research so far. Aug 23 '15 at 21:18
• Please provide more details. For example are you showing 1,10 or 100 different products? How often does the inventory change? Are the low and high levels the same for each SKU or different for different SKU's? Does inventory go from 0 to 100, or could one product have 100, 000 stock and another have a 10 stock? Aug 24 '15 at 2:14
• why do you want to represent a number with something other than a number? Aug 24 '15 at 9:31
• Can you make it clear whether you want to and expect the users to work out the exact stock figures (as suggested by your mockup) or whether you want to just give a rough display of stock level (like a progress inficator does for progress). Aug 24 '15 at 11:05

### Look at it a different way

You're trying to accurately show the current quantity. Perhaps users don't need the accuracy? Maybe it's about encouraging the correct user behaviour as quantities change.

• What user behaviours must change as a function of stock quantity?

For any given item, there are probably several quantities, or thresholds, at which user behaviour must change again.

A change in quantity might require users to: change the price, start back-ordering, request a new manufacturing run, ship only to preferred customers, short-ship to all customers, start selling a substitute product, initiate a stock transfer, notify key departments, and so on.

Once you find the behaviours that must change at certain thresholds, you can figure out how to depict each required behaviour in an intuitive way. Maybe you can do this with icons and text labels.

One advantage of focusing on user behaviour rather than stock quantity is that each item can have a different threshold for the same behaviour. For example, widgets might go on sale when inventory drops below 100 items, and wingdings might go on sale when inventory drops below 5.

It's even possible that some users don't need quantities at all—as long as the system helps them take the correct action. Or it may be sufficient to show a placebo quantity—a number that gets the desired behaviour from the users. Airlines often disclose their inventory only partially. The desired user behaviour is: "Book it now or release it back to inventory." A reservation system may disclose to web users and to other airlines that "We have at least 3 seats available now" without disclosing the actual total, because those totals would help the airline's competitors.

### To sum up

Consider the alternatives to exactness. Consider what you want users to do. Then provide information to encourage that behaviour.

• Thanks, Jerome. This is good advice. It made me think about what would be actually useful data, and I realised that relative movements like `+10%` or `-5%` would be useful to the stock controller. I will talk to the line operator and hear what kind of actionable insights they would consider valuable. Aug 25 '15 at 9:07
• Hi @Pate, what did the line operator say? Aug 26 '15 at 9:33

I recommend a heatmap for your case. It will be more conventional and much easier for users to read.

What would also help with displaying a big dispersion of values like 12000-300 is logarithmic scale.