diff --git a/tplus/client/clearingengine/admin.py b/tplus/client/clearingengine/admin.py
index fadf755..f1224d5 100644
--- a/tplus/client/clearingengine/admin.py
+++ b/tplus/client/clearingengine/admin.py
@@ -8,6 +8,7 @@
 
 from tplus.client.clearingengine.base import BaseClearingEngineClient
 from tplus.model.asset_identifier import AssetIdentifier
+from tplus.model.interest_rates import InterestRates
 from tplus.model.types import UserPublicKey
 from tplus.utils.user import User
 
@@ -227,3 +228,9 @@ async def set_trader_as_mm(
                 "signature": sig,
             },
         )
+
+    async def set_interest_rates(self, rates: list[InterestRates]):
+        await self._post(
+            "admin/interest/inject",
+            json_data={"request_id": 1, "rates": [r.model_dump(mode="json") for r in rates]},
+        )
diff --git a/tplus/model/interest_rates.py b/tplus/model/interest_rates.py
new file mode 100644
index 0000000..b9d5629
--- /dev/null
+++ b/tplus/model/interest_rates.py
@@ -0,0 +1,8 @@
+from pydantic import BaseModel
+
+
+class InterestRates(BaseModel):
+    asset_identifier: str
+    funding_rate: int
+    utilisation_rate: int
+    quote_utilisation_rate: int
diff --git a/tplus/model/user_inventory.py b/tplus/model/user_inventory.py
index 3c7306e..294a445 100644
--- a/tplus/model/user_inventory.py
+++ b/tplus/model/user_inventory.py
@@ -1,3 +1,4 @@
+from decimal import Decimal
 from typing import Literal
 
 from pydantic import BaseModel
@@ -6,14 +7,14 @@
 class Spot(BaseModel):
     """Represents a single spot account with multiple assets"""
 
-    spot_account_balance: dict[str, int]
+    spot_account_balance: dict[str, Decimal]
 
 
 class Balance(BaseModel):
     """Represents either credits or liabilities for given asset"""
 
-    credits: int
-    liabilities: int
+    credits: Decimal
+    liabilities: Decimal
 
 
 class MarginPosition(BaseModel):