I wound up coming up with a solution. Any spaces at the start of the field will be truncated when Splunk builds that chart. I made a sort_order field that adds spaces to the start of the field value. The more spaces, the earlier in the chart order the field is placed. Here's the code now: <Base Search>
| eval sort_order=case(
income=="$24,000 and under"," $24,000 and under",
income=="$25,000 - $39,999"," $25,000 - $39,999",
income=="$40,000 - $79,999"," $40,000 - $79,999",
income=="$80,000 - $119,999"," $80,000 - $119,999",
income=="$120,000 - $199,999"," $120,000 - $199,999",
income=="$200,000 or more","$200,000 or more")
| chart count by sort_order
... View more