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Most businesses have more data than they know what to do with. Sales figures, customer records, website numbers, and campaign reports pile up, but turning them into a clear answer is harder than it sounds, and many people aren’t sure where to start.
The steps for data analysis give you a repeatable way to do it. This guide walks through the eight steps, using one example, so you can see how each step works in practice. But before that, let’s understand what data analysis actually is.
What is data analysis?
Data analysis is the work of examining data to answer a specific question and decide what to do next. It turns raw data into something you can act on.
You need it whenever a decision depends on information you can’t read at a glance. Typical cases could be about knowing why your sales dropped, checking whether a campaign worked, or deciding where to cut costs.
You’ll also see this process called the data analytics. The names differ, but the work is the same.
Step 1: Define the problem
What it is: Deciding exactly what you want to find out, before you look at any data.
How to do it:
- Write one specific question, a goal you can measure, and a deadline. “Look at our sales data” is not a question. “Find out why repeat orders dropped last quarter, and recommend one fix within two weeks” is.
- Define your terms. “Repeat order” could mean a second order within 90 days, or any order after the first. Pick one and write it down, because different definitions give different numbers.
- Ask what decision the answer will change. If nobody will act on the result, the question needs rework.
Step 2: Source the data
What it is: Finding and pulling together the data you need to answer the question.
How to do it:
- List where the data lives. Internal sources are usually your order system, CRM, finance software, and the email or ads tools. External sources, such as public datasets, only matter if the question needs them.
- Check that the date range covers the period you’re asking about, plus some earlier time for comparison.
- Check that you can match the same record across sources, for example the same customer by email address or customer ID.
- Check what each column means. “Order date” might be the day it was placed or the day it shipped.
If this data sits in many tools and someone copies it together by hand every month, that gets slow and error-prone. Connecting the systems through software integration removes most of that repeat work.
Step 3: Clean the data
What it is: Fixing the problems in the raw data before you analyze anything.
Common problems to look for:
- Duplicates: the same customer entered twice, for instance with a capital letter in one email address, so they look like two people.
- Mixed formats: dates written day-month in some rows and month-day in others, or amounts with and without currency symbols.
- Blanks and placeholders: empty cells, or entries like “N/A” and “-” that should mean zero or “unknown”.
- Inconsistent spelling: the same product or city written three different ways.
How to do it:
- In Excel: make text consistent with
=LOWER()or=TRIM(), then use Data → Remove Duplicates on rows that are true duplicates. Convert date columns to one format, and use Find & Replace to standardize placeholders such as “N/A”. - In Google Sheets: highlight the duplicates first so you can review them before removing anything. This guide shows how to highlight duplicates in Google Sheets. Then remove the true duplicates with Data → Data cleanup → Remove duplicates.
- In Power BI: choose Transform data to open Power Query, then use Remove Duplicates, set the column data types, and Replace Values. Each change is saved as a step, so it runs again automatically when the data refreshes.
Step 4: Explore the data
What it is: Getting a feel for the data before you answer the question, so you catch problems early.
How to do it: Three checks cover most of it:
- Do the totals match a number you trust? Compare your total orders or revenue with what finance reports. If they differ, find out why before going further.
- What do the extremes look like? Sort each key column from smallest to largest. A value a hundred times the average is either a real outlier, such as one very large customer, or a typo. Decide which, and note how you treated it.
- How do the numbers move over time? Work out the key figure by month or week and chart it as a line. This confirms whether the change you’re investigating is real and shows when it starts.
Step 5: Apply analytical methods
What it is: Going after the question by splitting the data in ways that might explain the pattern and comparing the groups.
How to do it:
- Start simple. Compare the figure you care about across time periods, product categories, regions, customer types, or sales channels, and see where the difference sits.
- Narrow down. If a number fell overall, find out whether it fell everywhere or mostly in one group. That’s usually where the answer is.
- Use heavier methods only when the question needs them. Regression shows how one factor affects another. Classification sorts records into groups. Clustering finds natural groupings you didn’t define in advance.
If you want to predict what’s likely to happen next, such as which customers may stop buying, that’s where AI and machine learning comes in.
Step 6: Interpret the results
What it is: Testing whether your result is actually an answer.
How to do it: Ask three questions:
- Does it answer the question from Step 1? A finding that doesn’t point to an action isn’t done yet.
- Could something else explain it? A promotion, a change in season, a new tracking setup, or a one-off event can all create a pattern that isn’t what it seems. Check the likely alternatives.
- Is it real, or could it be noise? Look at the size of each group. Check whether the difference is large enough to matter and whether the data supports it. Larger samples can reduce random uncertainty, but they don’t eliminate sampling bias, measurement errors, or other sources of misleading results.
Be clear about limits too. If your data only covers part of your customers, say so. And if the data doesn’t give a clear answer, say that. It’s a valid result.
Step 7: Visualize the data
What it is: Turning your findings into charts and visuals that someone else can read in seconds.
How to do it:
- One chart per message.
- Use a title that states the finding (“Online sales grew while in-store sales stayed flat”), not a label (“Sales by channel”).
- Use lines for trends over time and bars for comparisons.
- Remove anything that doesn’t help the reader: extra gridlines, decorative colors, unused legends.
Step 8: Make data-driven decisions
What it is: Turning the finding into an action, and keeping a record of how you got there.
How to do it:
- Give a clear recommendation, with an owner and a date to check the result. For instance: try the change for four weeks, name who is responsible, and review the numbers again at the end.
- Write down what you did, so someone else can repeat it or check it. At minimum, record the question and definitions, where each dataset came from and when it was pulled, the changes made during cleaning, and any assumptions and limits.
- When the review date arrives, go back and see whether the numbers moved.
Data analysis is a loop, not a straight line
The steps are listed in order, but real projects rarely run straight through. Exploring the data might show you need another source. Interpreting the results might send you back to clean the data differently. That’s normal. It’s a sign you’re checking your own work.
What are the types of data analysis?
The steps stay the same across projects, but what you do in Step 5 depends on the question.
- Descriptive analysis answers “what happened?” Example: sales fell last quarter.
- Diagnostic analysis answers “why did it happen?” Example: most of the fall came from one region.
- Predictive analysis answers “what is likely to happen next?” Example: which customers are likely to cancel.
- Prescriptive analysis answers “what should we do about it?” Example: offer a discount to the customers most at risk.
Most projects start with descriptive and diagnostic work. Predictive and prescriptive analysis usually needs more data and more specialist skills.
Which data analysis tool should you use?
- Excel or Google Sheets: small datasets, quick checks, and learning the process.
- SQL: pulling and filtering data from databases.
- Power BI or Tableau: dashboards and sharing results with others.
- Python or R: large datasets, repeat analysis, and modelling.
You don’t need all of them. Start with the one you already know, and add the next when the work outgrows it.
Common mistakes to avoid
- Starting with the data before the question is clear
- Skipping the cleaning step because the data “looks fine”
- Not checking totals against a trusted source
- Reporting a pattern without checking what else could explain it
- Finishing with a chart and no recommendation
How NextGenSoft can help
A spreadsheet and a clear question are enough for many analysis projects. Help usually becomes worth considering at a few points:
- The data is spread across many systems and takes hours to pull together each time. Connecting those systems, as covered in Step 2, makes the data ready when you need it.
- You want to go beyond reporting to predicting what’s likely to happen, such as which customers may stop buying. That’s the kind of work our data science solution delivers.
- The analysis has to run regularly, not just once, and needs to be set up so the results stay reliable.
If any of that sounds like your situation, you can get in touch with us through the contact page.
Frequently asked questions
1. What are the steps of data analysis?
Answer: Define the problem, source the data, clean it, explore it, apply analytical methods, interpret the results, visualize them, and make a decision. Some analysis requires five, six, or seven steps by combining a few of these, but the use case is same.
2. What is the difference between data analysis and data analytics?
Answer: In everyday use, people treat them as the same thing. Where a distinction is made, analysis means examining a dataset to answer a question, and analytics is the wider practice, including the tools and processes behind it.
3. Which step takes the longest?
Answer: Usually cleaning. Getting the data into shape often takes longer than analyzing it, which is why a clear question and reliable sources save so much time.
4. Do I need to know coding to do data analysis?
Answer: No. You can complete all eight steps in Excel or Power BI. Coding in SQL or Python becomes useful when the data gets large or the analysis has to be repeated regularly.