As with many other types of graphs and charts, tally charts are one method of showing a certain amount of data in an easy-to-understand format. However, although effective in some ways, they are not so effective in others, leading them to not necessarily be the perfect choice for certain types of data. A tally chart is shown by drawing a vertical line for each number, and a diagonal line across the previous four lines whenever a multiple of five is reached.
Advantage -- Simplicity
Tally charts are simple to draw up and use. Rather than having to draw up an entire graph with measurements, or a chart which may require angles and certain equations to work out, a tally chart just consists of lines. Because of this, they are a popular choice of graph to be used by children. This also means that they are good to use in situations where data needs to be collected quickly, or with as little hassle as possible.
Advantage -- Universality
Another advantage is that tally charts are universal. This means that they can be used in any language or dialect, regardless of the alphabet, language or number system used. The tally chart requires no form of writing at all, just lines and an ability to count, and so anywhere across the world they can be used, making them particularly useful if they need to be transferred globally.
Advantage -- Increasing values
The last advantage is that they are easier to write up than various other forms of charts and graphs. A tally chart is used specifically to count up numerically. If one was doing this with numbers, for example, then they would have to keep crossing out the previous number and writing down the next one, which eventually gets tiresome and isn’t a very ordered way of presenting data. With a tally chart, however, lines are added as data is added, so the data is kept structured and neat. This is particularly useful when tallying data such as points in sport.
Disadvantage -- Large numbers
Tally charts also have disadvantages. For instance, although tally charts are great at tallying up information such as points in sport or a count of a small amount of objects, they are useless at catering for larger volumes of data. For example, it would be a lot of effort to count up over 1000 objects, or points, by using a tally chart, as the process would take a long time and also a lot of space. For this reason they are much better to use with smaller numbers, and a graph with changeable axes would be more appropriate in this instance.
Disadvantage -- Limited
Another disadvantage is that by using tally charts you are very limited with the types of data you can collect. Tally charts are absolutely perfect for counting up whole numbers. However, they can’t accommodate for other types of numbers, such as decimals, fractions or minus numbers, as there are no symbols to show these. So, if the data you are collecting includes numbers other than whole numbers, a graph would again be more appropriate.
Disadvantage -- Not immediate
The last disadvantage of tally charts is that the visual collection of the data is not immediate. When we see a number, we immediately know what amount it means. However, if a tally chart has been used for a fair bit of data then, although it is quicker, one still has to tally up the information in their mind to count how much data the chart represents. So, reading the tally chart isn’t as simple as it could be and requires some time to do so.