How Do Line Graphs Work?
A line graph is a type of graph in which lines connect individual data points. It is sometimes referred to as a line plot or a line chart. Quantitative values are shown on a line graph for a given period. Line graphs are frequently used in finance to show an asset’s or security’s historical price behavior.
Line graphs can be contrasted with various data visualizations such as pie charts, bar charts, and candlestick charts (used in trading, for example).
Recognizing Line Graphs
Data point “markers,” joined by straight lines, are used in line graphs. The straight lines that connect these data points help with visualization. Although line graphs are used for many reasons in various fields, they are instrumental in creating a graphical representation of value changes over time.
In finance, line graphs are frequently used to illustrate values over time, such as shifts in asset prices, revenue statements from businesses, and the historical performance of key stock indices. They come into use when contrasting several securities as well. Investors in technical analysis, in particular, use line graphs to visualize trends, which can significantly help them in their assessments.
Line graphs have several drawbacks. For instance, line graphs can become illegible with too many data points. Additionally, it is simple to modify them to produce specific effects visually. For instance, by changing the range of data points on the axes, one can visually alter the apparent degree of change.
Building a Line Chart
The two axes that make up a line graph are the horizontal (x-axis) and vertical (y-axis). The spots where the axes intersect are (0,0), and each axis represents a distinct data type. Since its values are independent of whatever is measured, the x-axis is known as the independent axis. Since the values of the y-axis rely on those of the x-axis, it is known as the dependent axis.
The data measured along each axis should determine the label for that axis. Next, divide each axis into the proper number of days (e.g., day one, day two, etc.). For instance, the x-axis would show the time measured (trading days within the period), and the y-axis would show stock prices if the changes in a stock’s price over the preceding two weeks were being measured.
The stock’s closing price is the data point most frequently utilized in line graphs to track stock prices.
Assume, for instance, that the price of a particular stock was $30 on the first day of trade; this would produce a data point at (1, $30). The stock hit $35 on day two of trading, which produced a data point at (2, $35).
Plotting and connecting each data point with a line allows you to see how the numbers vary over time. The line would slope upward and to the right if the stock’s value increased daily. On the other hand, the line would slope rightward and downward if the stock price was continuously declining.
Sorts of Line Diagrams
Line graphs come in three primary varieties. Despite sharing core principles, each kind has a specific application and usage scenario that makes it the most appropriate.
Basic Line Diagram
The most fundamental kind of line graph is a simple line graph. In this graph, a single line connects each data point because only one dependent variable is under observation. The graph’s sole objective is to track the variable’s changes over time, with each point on the graph corresponding to the same item. Since only one variable is shown on this graph, comparing one variable to another is impossible.
The time axis (x-axis) in the example below represents time, while the y-axis shows the annual price change for all U.S. consumer goods. There is only one line on this graph of the Consumer Price Index, which displays the annual inflation rate because it evaluates a single collection of data—all goods.
Many Line Graphs
A multiple-line graph compares several dependent variables across one independent variable, usually time, by charting them on the graph. To differentiate between each data set, various colored lines are frequently applied to different dependent variables. No line crosses over between dependent variables; each line pertains only to the points in the specific data set it is part of.
For instance, the Consumer Price Index is displayed again in the line graph below. On the other hand, this graph displays the price changes for three distinct categories: commodities (green), medical care (red), and shelter (blue). This graph shows that in July 2022, the price growth for commodities was greater than that of the other two categories. However, housing and healthcare costs have generally seen more significant inflation during the last ten years.
Composite Line Diagram
Similar to a multiple-line graph, a compound line graph uses numerous variables. Nevertheless, the variables are sometimes piled on top of one another to display the entire number across all variables. Users are informed not only about the relationships between the variables but also about changes in the total.
The Environmental Protection Agency (EPA) provided the example below, showing five dependent variables ranging from arid land to extreme drought areas. Any blank space beneath the line graph representing the most severe drought data was colored dark red. Subsequent data sets were then plotted, shading the space beneath each of those lines with the corresponding color. Overall, this illustrates the correlation between descriptions of drought and the total percentage of U.S. land area classified into these categories annually.
Components of a Line Chart
The formatting and optional features of line graphs can change. The following traits are included in the best, most understandable line graphs:
Title: A title atop a line graph might serve as a concise explanation of what the graph shows. If the written context is not provided, the user will frequently rely on the title to better understand the pulled data. For example, “Level of U.S. Dry Land by Year, 2000–2015” would be a suitable title for the compound line graph. The title may also explicitly specify a timeframe or constraints for the data.
Mythology
The caption describes each dependent variable and shows how to tell apart various data sets. Every dependent variable in the above example is indicated with a different color. The legend is the box that describes the meaning of each hue.
Info
A line graph’s data points reference various sources linking independent and dependent variables. This is the data on your graph; it’s the thing that makes the dots on your chart link to form lines. As demonstrated above, there are instances where a single graph incorporates information from several data sets. Businesses may employ specialized data integrity analysts or roles akin to them to keep an eye on database activities to guarantee that data is valid and safeguarded.
Axis X
The collection of data that extends down the line graph’s bottom, horizontal, flat section is called the x-axis. The x-axis of most line graphs represents time; it might represent the weeks that have elapsed since a product launch, the months that make up a year, or anything else.
Axis Y
The collection of data that runs along the graph’s left-hand vertical axis is called the y-axis. This set of data appears on the right of some line graph iterations. These figures, in any event, count the objects being measured. Although there are situations where it makes more sense to start at a higher number, the graph may begin at zero.
Line The line is the last item. The line connects every data point inside a single dependent variable. The movement of this line illustrates how information changes over time. If all data sets are monitored across comparable periods, they can be compared to other lines. This line, despite its oversimplification, can tell management what needs to be done to enhance strategic planning or operations.
Making an Excel Line Graph
Excel has a line graph that you can use to show patterns over time. Line graphs are appropriate if your Excel chart’s horizontal axis (x-axis) has text labels, dates, or a few numeric labels. The steps to make an Excel line graph are as follows::. (If you want to use numerical labels, make sure cell A1 is empty before making the line graph.)
In Row 1, type the column headers you want. These columns will provide descriptions of the various data groups (for instance, in the example below, the headers distinguish the data by animal).
In Column A, enter the value of your x-axis. Due to the data’s year-based sorting, the first column of the example below lists the years 2017 through 2022.
Put your data in. Enter a pertinent figure in each cell that matches a header and year. In case there is no data, type ‘0’.
Choose the range (any range that includes those numbers) after entering your values. If you want labels and headers on your graph, choose the first row and first column. For instance, by choosing A1:D7, the y-axis may be labeled “Count of Animals,” while the x-axis can be labeled “Years.”
Click the line symbol (“Insert Line Chart”) in the Charts group on the Insert tab.
“Line with Markers” should be clicked. This will produce a line graph that resembles the one below, except that instead of marking each data point with a larger dot, a thinner line will connect them. You can change a lot of these formatting elements.
Functions of a Line Chart
A line graph is just one of many data visualization methods that work best for different applications. A line graph works well, depending on the underlying data, for:
Monitoring evolves. Typically, a line graph is plotted with the quantity of occurrence on the y-axis and the periods on the x-axis. Although line charges can be divided into days, weeks, months, or other lengths (e.g., days since a new CEO was hired), each period was a year.
They were monitoring more subtle changes. A graph’s range can be adjusted to zoom in on data more effectively than it might vary much. A line graph can be designed to have tiny increments on the y-axis, which makes it easier to see how little change has occurred over time than other types of charts.
Contrasting alterations across multiple groups. In the example above, it is easy to compare the quantity of three various costs in a single visual. Since every line is colored differently, it is possible to track and compare different kinds of data simultaneously without any problems.
Continuous data sets. A line graph must have at least one continuous variable since it depends on a single strain of uninterrupted data. This variable is often time. There is no purpose in linking each data point with a line for a non-continuous data set (such as the number of animals at the ten most prominent zoos in the world); a bar chart would be more appropriate.
Why Would Someone Use a Line Graph?
One way to monitor changes over several periods is with line graphs. Additionally, line graphs can be used as a comparison tool to examine changes for multiple groups over the same period.
How is a line a valuable graph in finance?
Because they are so good at visualizing trends over time, line graphs are helpful in the banking industry. For this reason, they are typically used to show how a stock performs over a given period.
Which Three Kinds of Line Graphs Are There?
There are three types of line graphs: compound, many, and straightforward. Each type of graph has a varying degree of dependent variables and how the user desires to portray the relationship between these variables.
What are the parts of a line graph?
Line graphs can be significantly customized regarding the title, labels, markers, line style, and other optional elements. All line graphs, however, have to include input data (dependent variables), an x-axis (independent variable), and a y-axis (amount of dependent variable). On the graph, a line connects the data points for each dependent variable that has been marked.
The Final Word
The line graph is among the data’s most significant graphical representations when examining data over time. Time is frequently used as the x-axis, and a numerical quantity is used as the y-axis in a line graph. The chart is a helpful tool for studying changes over time for one or more variables because all data points within a single dependent variable are connected with a line when data points are marked.
Conclusion
- A line graph joins data points that typically show quantitative values over time.
- Line graphs have two axes: the x-axis (horizontal) and the y-axis (vertical), which are represented graphically as (x,y).
- Line graphs are useful in technical analysis and investing because they allow users to visualize trends.
- While line graphs are used for various purposes, their most common function is to create a graphical representation of value changes over time.
- Line graphs are used in finance to provide visual representations of values over time, such as changes in the pricing of assets.
