diff --git a/src/commands/roi.rs b/src/commands/roi.rs
index 74577cf..06b5f8d 100644
--- a/src/commands/roi.rs
+++ b/src/commands/roi.rs
@@ -206,7 +206,7 @@ pub fn execute(
         // Period: 5.41 years.
         // Annualized TWR: 10.12%
         let mut total_twr = 1.0;
-        let mut irr = irr(&cash_flows);
+        let irr = irr(&cash_flows);
         for p in periods.iter() {
             total_twr *= 1.0 + p.twr().to_f64().unwrap();
             // dbg!(&total_twr);
diff --git a/src/error.rs b/src/error.rs
index fff74f1..4d90fed 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -44,7 +44,6 @@ impl Display for TimeParseError {
 
 #[derive(Debug)]
 pub enum LedgerError {
-    EmptyPostingShouldBeLast,
     AliasNotInList(String),
     TooManyEmptyPostings(usize),
 }
@@ -52,9 +51,6 @@ impl Error for LedgerError {}
 impl Display for LedgerError {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
-            LedgerError::EmptyPostingShouldBeLast => {
-                write!(f, "{}", "Empty posting should be last".red())
-            }
             LedgerError::AliasNotInList(x) => write!(f, "Alias not found: {}", x),
             LedgerError::TooManyEmptyPostings(_) => {
                 write!(f, "{}", "Too many empty postings".red())
@@ -118,3 +114,36 @@ impl<'a> fmt::Display for ColoredStrings<'a> {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use structopt::StructOpt;
+
+    use super::LedgerError;
+    use crate::{parser::Tokenizer, CommonOpts};
+
+    #[test]
+    fn error_empty_posting_last() {
+        let mut tokenizer = Tokenizer::from(
+            "2021-06-05 Flight
+        Assets:Checking
+        Expenses:Comissions
+        Expenses:Travel      200 EUR"
+                .to_string(),
+        );
+        let options = CommonOpts::from_iter(["", "-f", ""].iter());
+        let parsed = tokenizer.tokenize(&options);
+        let ledger = parsed.to_ledger(&options);
+        assert!(ledger.is_err());
+        if let Err(err) = ledger {
+            let ledger_error = err.downcast_ref::<LedgerError>().unwrap();
+            match ledger_error {
+                LedgerError::TooManyEmptyPostings(x) => (),
+                other => {
+                    dbg!(other);
+                    panic!("Too many empty postings");
+                }
+            }
+        }
+    }
+}