This example visualizes monthly atmospheric CO2 concentrations from the Keeling Curve dataset, highlighting raw measurements, seasonally adjusted values, and smoothed fits over time. The code loads CSV data, parses date fields into JavaScript Date objects, and replaces missing values (marked as -99.99) with NaN. It then displays a single data row as formatted JSON in a `<pre>` element, using `JSON.stringify` to show the parsed structure. The example demonstrates data preprocessing and inspection for further visualization.