Refactor financial chart implementation

js/charts/ppmt_ip.js

@@ -1,6 +1,6 @@
 import { col } from '../csv.js';
 import {
-  PALETTE, FONT, axisCommon, periodAxis, titleStyle, legendStyle,
+  PALETTE, FONT, axisCommon, categoryAxis, titleStyle, legendStyle,
   lineSeries, footnote, watermarks, LAYOUT,
 } from '../theme.js';
 
@@ -49,10 +49,7 @@ export function ipChart(rows, { width, height }) {
       ...legendStyle,
       top: LAYOUT.legendTop,
       itemGap: 20,
-      data: rows.map(r => ({
-        name: r.ip,
-        icon: 'emptyCircle',  // 折线图：空心圆圈
-      })),
+      data: rows.map((row) => row.ip),
     },
     grid: { left: 78, right: 56, top: LAYOUT.gridTop, bottom: 70 },
     tooltip: {
@@ -60,7 +57,14 @@ export function ipChart(rows, { width, height }) {
       valueFormatter: (v) => `${v.toFixed(2)} 亿元`,
       textStyle: { fontFamily: FONT },
     },
-    xAxis: { ...periodAxis, data: periods },
+    xAxis: {
+      ...categoryAxis,
+      data: periods,
+      axisLabel: {
+        ...categoryAxis.axisLabel,
+        formatter: (value) => String(value).replace(/^20/, ''),
+      },
+    },
     yAxis: {
       ...axisCommon,
       type: 'value',