# The Cost of Cleaning

We’ve frequently mentioned that people who work on data projects tell us that frequently, 80% of their projects are consumed by data preparation and cleaning, so it is interesting to get this data point from Kaggle:

(2) How long is a typical project?
When working with a top 0.5% data scientist, projects take just eight to 40 hours ($3k to$12k). Projects are finished in closer to eight hours for clean data and closer to 40 hours when the data requires cleaning.

So, in this anecdote, with some squinty-eyed interpretation,  data cleaning requires 32 out of 40 hours. Dead on. And, by the way, that’s 32 hours at \$300 per hour.

Fortunately, the library has a plan to reduce the cost of data cleaning and preparation.