diff --git a/Assets/Scripts/Attribute.cs b/Assets/Scripts/Attribute.cs
index c8c9090..9d2ac95 100644
--- a/Assets/Scripts/Attribute.cs
+++ b/Assets/Scripts/Attribute.cs
@@ -2,35 +2,26 @@ using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
-public struct Attribute
+public class Attribute : ScriptableObject
 {
-    [SerializeField]
-    private long _base;
+    public long Base { get; set; }
+    public long BaseBonus { get; set; }
+    public long PermyriadBonus { get; set; }
+    public long FlatBonus { get; set; }
 
-    public Attribute(long stat)
-    {
-        _base = stat;
-    }
-
-    /// <summary>
-    /// Permanently increase the stat value.
-    /// </summary>
-    /// <param name="by">Increase amount.</param>
-    public void LevelUp(long by)
-    {
-        _base += by;
-    }
+    public long Value => Calc(Base, BaseBonus, PermyriadBonus, FlatBonus);
 
     /// <summary>
     /// Calculates the stat value with accumulated buff and debuff modifiers.
     /// </summary>
+    /// <param name="baseValue">Base value.</param>
     /// <param name="baseBonus">Additive bonus applied before multiplicative scaling.</param>
     /// <param name="permyriadBonus">Multiplicative scaling in hundredths of a percent. E.g., 625 permyriad corresponds to 6.25%.</param>
     /// <param name="flatBonus">Additive bonus applied after multiplicative scaling.</param>
     /// <returns>(base + baseBonus) * (100% + permyriadBonus) + flatBonus, bounded below by 0.</returns>
-    public long Calc(long baseBonus, long permyriadBonus, long flatBonus)
+    public static long Calc(long baseValue, long baseBonus, long permyriadBonus, long flatBonus)
     {
-        var r = _base + baseBonus;
+        var r = baseValue + baseBonus;
         var m = permyriadBonus + 10000;
         r = r * (m / 10000) + (r / 10000) * (m % 10000) + flatBonus;
         if (r <= 0)
diff --git a/Assets/Tests/AttributeTest.cs b/Assets/Tests/AttributeTest.cs
index 8668e08..f4b216c 100644
--- a/Assets/Tests/AttributeTest.cs
+++ b/Assets/Tests/AttributeTest.cs
@@ -7,19 +7,21 @@ using UnityEngine.TestTools;
 public class AttributeTest
 {
     [Test]
-    [TestCase(1000000, 0, 0, 0, 0, ExpectedResult = 1000000)]
-    [TestCase(1000000, 1, 0, 0, 0, ExpectedResult = 1000001)]
-    [TestCase(1000000, 0, 2, 0, 0, ExpectedResult = 1000002)]
-    [TestCase(1000000, 0, 0, 10000, 0, ExpectedResult = 2000000)]
-    [TestCase(1000000, 0, 0, 0, 3, ExpectedResult = 1000003)]
-    [TestCase(0, 1000000, 1000000, 5000, 1000, ExpectedResult = 3001000)]
-    [TestCase(1000000, 0, 0, -10000, 0, ExpectedResult = 0)]
-    [TestCase(1000000, 0, 0, -20000, 0, ExpectedResult = 0)]
-    [TestCase(1000000, 0, 0, -20000, 50, ExpectedResult = 0)]
-    public long Calc(long startStat, long levelUp, long baseBonus, long permyriadBonus, long flatBonus)
+    [TestCase(1000000, 0, 0, 0, ExpectedResult = 1000000)]
+    [TestCase(1000000, 1, 0, 0, ExpectedResult = 1000001)]
+    [TestCase(1000000, 0, 2, 0, ExpectedResult = 1000200)]
+    [TestCase(1000000, 0, 0, 10000, ExpectedResult = 1010000)]
+    [TestCase(0, 1000000, 5000, 1000000, ExpectedResult = 2500000)]
+    [TestCase(1000000, 0, -10000, 0, ExpectedResult = 0)]
+    [TestCase(1000000, 0, -20000, 0, ExpectedResult = 0)]
+    [TestCase(1000000, 0, -20000, 0, ExpectedResult = 0)]
+    public long Value(long startStat, long baseBonus, long permyriadBonus, long flatBonus)
     {
-        var attr = new Attribute(startStat);
-        attr.LevelUp(levelUp);
-        return attr.Calc(baseBonus, permyriadBonus, flatBonus);
+        var attr = ScriptableObject.CreateInstance<Attribute>();
+        attr.Base = startStat;
+        attr.BaseBonus = baseBonus;
+        attr.PermyriadBonus = permyriadBonus;
+        attr.FlatBonus = flatBonus;
+        return attr.Value;
     }
 }