Can't sort this column in Excel — hidden spaces and text-numbers cause
You sort the column and some values land in the wrong order, or all the way at the bottom regardless of their size. Excel sorts numbers and text-that-looks-like-numbers as two separate groups — and a leading or trailing space changes which group a value falls into. Drop your file in below to see which cells are the odd ones out.
Excel sorts by data type first, value second
An ascending sort in Excel doesn't just compare values — it groups by type first: numbers, then text, then logical values, then errors, always in that order (descending just reverses each group's internal order, but numbers still cluster separately from text). A column that looks like a clean list of numbers can actually be a mix of real numbers (right-aligned by default) and numbers stored as text (left-aligned, often flagged with a small green triangle in the corner). Sort it, and every text-number sinks to the bottom of the column — or the top of a descending sort — as a block, regardless of its numeric value.
Where the text-numbers come from
This almost always traces back to how the data arrived: values pasted from a web page or PDF, imported from a CSV where a column had a leading zero or a plus sign that made Excel default it to text, or entered with a leading apostrophe at some point to "protect" the formatting. Once a cell is text, typing a formula-visible number into it doesn't convert it — the underlying type stays text until it's explicitly converted.
The hidden-space complication
Even among genuinely text values, a cell with a trailing space — a regular space or, more stubbornly, a non-breaking space (Unicode character 160, common in data copied from websites) — sorts differently than the same text without it, because sorting compares strings character by character and a space is a real character in that comparison.
How to fix it
Select the column, use Data → Text to Columns → Finish (with no delimiter changes) to force text-numbers back into real numbers in one pass, and separately run TRIM/CLEAN or Find & Replace to strip stray spaces. Upload your file above first and the checker will flag exactly which cells in the column are text-typed versus numeric, and which carry leading or trailing whitespace.