diff --git a/src/hyperfine/benchmark.rs b/src/hyperfine/benchmark.rs
index 181609a..926b41e 100644
--- a/src/hyperfine/benchmark.rs
+++ b/src/hyperfine/benchmark.rs
@@ -146,7 +146,7 @@ pub fn mean_shell_spawning_time(
     }
 
     progress_bar.as_ref().map(|bar| bar.finish_and_clear());
-    
+
     Ok(TimingResult {
         time_real: mean(&times_real),
         time_user: mean(&times_user),
@@ -225,7 +225,7 @@ pub fn run_benchmark(
             &values[num]
         };
         match cmd.get_parameter() {
-            Some((param, value)) => Command::new_parametrized(preparation_command, param, value.clone()),
+            Some((param, value)) => Command::new_parametrized(preparation_command, param, *value),
             None => Command::new(preparation_command),
         }
     });
@@ -252,10 +252,8 @@ pub fn run_benchmark(
                 None,
             )?;
             progress_bar.as_ref().map(|bar| bar.inc(1));
-    
         }
         progress_bar.as_ref().map(|bar| bar.finish_and_clear());
-        
     }
 
     // Set up progress bar (and spinner for initial measurement)
@@ -308,7 +306,7 @@ pub fn run_benchmark(
     // Re-configure the progress bar
     progress_bar.as_ref().map(|bar| bar.set_length(count));
     progress_bar.as_ref().map(|bar| bar.inc(1));
-    
+
     // Gather statistics
     for _ in 0..count_remaining {
         run_preparation_command(&options.shell, &prepare_cmd, options.show_output)?;
@@ -339,7 +337,6 @@ pub fn run_benchmark(
 
     progress_bar.as_ref().map(|bar| bar.finish_and_clear());
 
-
     // Compute statistical quantities
     let t_num = times_real.len();
     let t_mean = mean(&times_real);
@@ -421,7 +418,7 @@ pub fn run_benchmark(
             .cleanup_command
             .as_ref()
             .map(|cleanup_command| match cmd.get_parameter() {
-                Some((param, value)) => Command::new_parametrized(cleanup_command, param, value.clone()),
+                Some((param, value)) => Command::new_parametrized(cleanup_command, param, *value),
                 None => Command::new(cleanup_command),
             });
     run_cleanup_command(&options.shell, &cleanup_cmd, options.show_output)?;
@@ -436,6 +433,6 @@ pub fn run_benchmark(
         t_min,
         t_max,
         times_real,
-        cmd.get_parameter().as_ref().map(|p| p.1.clone()),
+        cmd.get_parameter().map(|p| p.1.to_string()),
     ))
 }
diff --git a/src/hyperfine/parameter_range.rs b/src/hyperfine/parameter_range.rs
index c6f4144..5f73580 100644
--- a/src/hyperfine/parameter_range.rs
+++ b/src/hyperfine/parameter_range.rs
@@ -1,5 +1,5 @@
 use crate::hyperfine::error::ParameterScanError;
-use crate::hyperfine::types::{Command, NumericType};
+use crate::hyperfine::types::{Command, NumericType, ParameterValue};
 use clap::Values;
 use rust_decimal::Decimal;
 use std::ops::{Add, AddAssign, Div, Sub};
@@ -92,7 +92,11 @@ fn build_parameterized_commands<'a, T: Numeric>(
 
     for value in param_range {
         for cmd in &command_strings {
-            commands.push(Command::new_parametrized(cmd, param_name, value.into().to_string()));
+            commands.push(Command::new_parametrized(
+                cmd,
+                param_name,
+                ParameterValue::Numeric(value.into()),
+            ));
         }
     }
     Ok(commands)
diff --git a/src/hyperfine/types.rs b/src/hyperfine/types.rs
index 70e3c38..c34b029 100644
--- a/src/hyperfine/types.rs
+++ b/src/hyperfine/types.rs
@@ -39,6 +39,21 @@ impl Into<NumericType> for Decimal {
     }
 }
 
+#[derive(Debug, Clone, Copy)]
+pub enum ParameterValue<'a> {
+    Text(&'a str),
+    Numeric(NumericType),
+}
+
+impl<'a> ToString for ParameterValue<'a> {
+    fn to_string(&self) -> String {
+        match self {
+            ParameterValue::Text(value) => value.to_string(),
+            ParameterValue::Numeric(value) => value.to_string(),
+        }
+    }
+}
+
 /// A command that should be benchmarked.
 #[derive(Debug, Clone)]
 pub struct Command<'a> {
@@ -46,7 +61,7 @@ pub struct Command<'a> {
     expression: &'a str,
 
     /// A possible parameter value.
-    parameter: Option<(&'a str, String)>,
+    parameter: Option<(&'a str, ParameterValue<'a>)>,
 }
 
 impl<'a> Command<'a> {
@@ -60,7 +75,7 @@ impl<'a> Command<'a> {
     pub fn new_parametrized(
         expression: &'a str,
         parameter: &'a str,
-        value: String,
+        value: ParameterValue<'a>,
     ) -> Command<'a> {
         Command {
             expression,
@@ -78,7 +93,7 @@ impl<'a> Command<'a> {
         }
     }
 
-    pub fn get_parameter(&self) -> &Option<(&'a str, String)> {
+    pub fn get_parameter(&self) -> &Option<(&'a str, ParameterValue<'a>)> {
         &self.parameter
     }
 }
diff --git a/src/main.rs b/src/main.rs
index 95c4220..40f0668 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,7 +16,7 @@ use crate::hyperfine::export::{ExportManager, ExportType};
 use crate::hyperfine::internal::write_benchmark_comparison;
 use crate::hyperfine::parameter_range::get_parameterized_commands;
 use crate::hyperfine::types::{
-    BenchmarkResult, CmdFailureAction, Command, HyperfineOptions, OutputStyleOption,
+    BenchmarkResult, CmdFailureAction, Command, HyperfineOptions, OutputStyleOption, ParameterValue,
 };
 use crate::hyperfine::units::Unit;
 
@@ -219,7 +219,11 @@ fn build_commands<'a>(matches: &'a ArgMatches<'_>) -> Vec<Command<'a>> {
 
         for value in param_list {
             for cmd in &command_list {
-                commands.push(Command::new_parametrized(cmd, param_name, value.to_string()));
+                commands.push(Command::new_parametrized(
+                    cmd,
+                    param_name,
+                    ParameterValue::Text(value),
+                ));
             }
         }