Percentage change
Percentage change is the relative difference between an initial and later value, expressed as a percentage of the initial value.
Data Storytelling with Altair and AI
A percentage increase is a measure of relative growth calculated by dividing the change in a quantity by its original value and expressing the result as a percentage.
- How it is used
- Uses percentage change to compare tourist-arrival growth across countries when absolute values obscure relative performance.
- How deep it goes
- Defines the formula and implements a per-country 1994-baseline calculation, then plots and labels the resulting values.
- Examples
- Uses tourist arrivals for Portugal, Germany, and other countries from 1994 through 2018.
- What you can do after
- Apply it via pandas and Altair to calculate baseline-relative growth and communicate it in a focused line chart.
Read how Data Storytelling with Altair and AI explains percentage change →
The Well-Grounded Data Analyst
Percentage change is the relative increase or decrease between an initial value and a later value, expressed as a percentage.
- How it is used
- Uses relative sales-volume movement to identify product performance that absolute changes may obscure.
- How deep it goes
- Calculates, visualizes, cleans, and qualifies percentage change, while stopping short of a general statistical treatment.
- Examples
- Contrasts sales changes from one to five items and from 500 to 1,000 items, then filters product performers by volume thresholds.
- What you can do after
- Apply it via pandas and NumPy to calculate, visualize, clean, and filter month-on-month product-sales changes.
Read how The Well-Grounded Data Analyst explains percentage change →
Investing for Programmers
A percentage change is the relative increase or decrease in a quantity expressed as a percentage of its original value.
- How it is used
- Compares stock performance across assets and time frames within an asset-monitoring workflow.
- How deep it goes
- Contrasts percentage and dollar gains with concrete values but stops short of implementation or formula derivation.
- Examples
- Uses Company A and Company B to contrast $300 and $250 gains with 30% and 50% returns.
- What you can do after
- Evaluate/understand asset performance using relative returns rather than relying only on dollar changes.
Read how Investing for Programmers explains percentage change →
Related concepts
- volumemeasures · A volume metric quantifies the amount, frequency, or level of activity, transactions, units, or other measured phenomena within a specified scope and period.
- historical returnproduces · A historical return is the realized percentage change in an investment's value over a completed past period.
- evaluationmeasured by · Evaluation is the systematic assessment of a system, result, or approach against relevant criteria, evidence, or objectives.
- visualizationaddresses · Visualization is the representation of data, information, or concepts in visual form to support inspection, interpretation, analysis, or communication.
- tourist arrivalsmeasures · Tourist arrivals are recorded entries or visits by tourists to a destination or accommodation establishment during a specified period.
- investingproduces · Investing is the allocation of money or other resources to an asset, venture, or undertaking with the expectation of obtaining a future benefit or return.
These guides are generated from the text of Manning books by Manning's knowledge graph and link to the sections they draw on. The full books are available on liveBook and at manning.com.