Color code financial statement YoY columns

Green for improvement, red for decline. Cost/expense rows use
inverse logic (decline = green). Value cells retain neutral styling.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 82 insertions, 30 deletions

diff --git a/components/financials.py b/components/financials.py
index 547aedb..828f256 100644
--- a/components/financials.py
+++ b/components/financials.py
@@ -1,33 +1,21 @@
 """Financial statements — Income Statement, Balance Sheet, Cash Flow."""
+import numpy as np
 import pandas as pd
 import streamlit as st
 from services.data_service import get_income_statement, get_balance_sheet, get_cash_flow
 from utils.formatters import fmt_large
 
+# Rows where a decline is actually good (e.g. costs, expenses)
+_INVERSE_ROWS = {
+    "cost of revenue", "cost of goods sold", "operating expenses",
+    "selling general administrative", "research development",
+    "interest expense", "income tax expense", "total expenses",
+    "reconciled cost of revenue",
+}
 
-def _format_statement(df: pd.DataFrame) -> pd.DataFrame:
-    """Format a yfinance financial statement for display."""
-    if df.empty:
-        return df
 
-    # Columns are datetime; convert to year strings
-    df = df.copy()
-    df.columns = [str(c)[:10] for c in df.columns]
-
-    # Add YoY % change columns if >= 2 periods
-    cols = list(df.columns)
-    result = pd.DataFrame(index=df.index)
-
-    for i, col in enumerate(cols):
-        result[col] = df[col].apply(_fmt_cell)
-        if i + 1 < len(cols):
-            prev_col = cols[i + 1]
-            yoy = df.apply(
-                lambda row: _yoy_pct(row[col], row[prev_col]), axis=1
-            )
-            result[f"YoY {col[:4]}"] = yoy
-
-    return result
+def _is_inverse(label: str) -> bool:
+    return label.strip().lower() in _INVERSE_ROWS
 
 
 def _fmt_cell(value) -> str:
@@ -38,16 +26,77 @@ def _fmt_cell(value) -> str:
     return fmt_large(v)
 
 
-def _yoy_pct(current, previous) -> str:
+def _yoy_raw(current, previous):
+    """Return raw float YoY % change, or None."""
     try:
         c, p = float(current), float(previous)
         if p == 0:
-            return "—"
-        pct = (c - p) / abs(p) * 100
-        arrow = "▲" if pct >= 0 else "▼"
-        return f"{arrow} {abs(pct):.1f}%"
+            return None
+        return (c - p) / abs(p) * 100
     except (TypeError, ValueError):
+        return None
+
+
+def _yoy_str(pct) -> str:
+    if pct is None:
         return "—"
+    arrow = "▲" if pct >= 0 else "▼"
+    return f"{arrow} {abs(pct):.1f}%"
+
+
+def _build_statement(df: pd.DataFrame):
+    """
+    Returns (display_df, color_df).
+    display_df: formatted string DataFrame for rendering.
+    color_df:   same shape, cells are 'green', 'red', or '' for styling.
+    """
+    df = df.copy()
+    df.columns = [str(c)[:10] for c in df.columns]
+    cols = list(df.columns)
+
+    display = pd.DataFrame(index=df.index)
+    colors = pd.DataFrame(index=df.index)
+
+    for i, col in enumerate(cols):
+        display[col] = df[col].apply(_fmt_cell)
+        colors[col] = ""
+
+        if i + 1 < len(cols):
+            prev_col = cols[i + 1]
+            yoy_label = f"YoY {col[:4]}"
+
+            raw_yoy = df.apply(lambda row: _yoy_raw(row[col], row[prev_col]), axis=1)
+            display[yoy_label] = raw_yoy.apply(_yoy_str)
+
+            def cell_color(row_label, pct):
+                if pct is None:
+                    return ""
+                inverse = _is_inverse(row_label)
+                positive_change = pct >= 0
+                good = positive_change if not inverse else not positive_change
+                return "green" if good else "red"
+
+            colors[yoy_label] = pd.Series(
+                [cell_color(idx, pct) for idx, pct in zip(df.index, raw_yoy)],
+                index=df.index,
+            )
+
+    return display, colors
+
+
+def _style(display: pd.DataFrame, colors: pd.DataFrame):
+    GREEN_BG = "background-color: rgba(46, 204, 113, 0.18); color: #7ce3a1;"
+    RED_BG   = "background-color: rgba(231, 76,  60,  0.18); color: #ff8a8a;"
+
+    def apply_colors(row):
+        return [
+            GREEN_BG if colors.loc[row.name, col] == "green"
+            else RED_BG if colors.loc[row.name, col] == "red"
+            else ""
+            for col in display.columns
+        ]
+
+    return display.style.apply(apply_colors, axis=1)
 
 
 def render_financials(ticker: str):
@@ -65,18 +114,21 @@ def render_financials(ticker: str):
         if df.empty:
             st.info("Income statement data unavailable.")
         else:
-            st.dataframe(_format_statement(df), use_container_width=True)
+            display, colors = _build_statement(df)
+            st.dataframe(_style(display, colors), use_container_width=True)
 
     with tab_balance:
         df = get_balance_sheet(ticker, quarterly=quarterly)
         if df.empty:
             st.info("Balance sheet data unavailable.")
         else:
-            st.dataframe(_format_statement(df), use_container_width=True)
+            display, colors = _build_statement(df)
+            st.dataframe(_style(display, colors), use_container_width=True)
 
     with tab_cashflow:
         df = get_cash_flow(ticker, quarterly=quarterly)
         if df.empty:
             st.info("Cash flow data unavailable.")
         else:
-            st.dataframe(_format_statement(df), use_container_width=True)
+            display, colors = _build_statement(df)
+            st.dataframe(_style(display, colors), use_container_width=True)