diff --git a/.devcontainer/ui-lovelace.yaml b/.devcontainer/ui-lovelace.yaml
index cd4c32e..a259715 100644
--- a/.devcontainer/ui-lovelace.yaml
+++ b/.devcontainer/ui-lovelace.yaml
@@ -69,11 +69,40 @@ views:
             curve: straight
 
       - type: custom:apexcharts-card
-        hours_to_show: 24
+        hours_to_show: 48
         series:
-          - entity: sensor.humidity
+          - entity: sensor.random0_100
+            name: AVG
             curve: smooth
             type: area
             group_by:
-              duration: 5h
+              duration: 1h
               func: avg
+          - entity: sensor.random0_100
+            curve: smooth
+            name: MIN
+            type: area
+            group_by:
+              duration: 1h
+              func: min
+          - entity: sensor.random0_100
+            curve: smooth
+            name: MAX
+            type: area
+            group_by:
+              duration: 1h
+              func: max
+          - entity: sensor.random0_100
+            curve: smooth
+            name: LAST
+            type: area
+            group_by:
+              duration: 3h
+              func: last
+          - entity: sensor.random0_100
+            curve: smooth
+            name: FIRST
+            type: area
+            group_by:
+              duration: 3h
+              func: first
diff --git a/src/apex-layouts.ts b/src/apex-layouts.ts
index d3ffaf5..9fe7243 100644
--- a/src/apex-layouts.ts
+++ b/src/apex-layouts.ts
@@ -1,5 +1,5 @@
 import { HomeAssistant } from 'custom-card-helpers';
-import { moment } from './const';
+import { DEFAULT_COLORS, moment } from './const';
 import { ChartCardConfig } from './types';
 import { computeName, computeUom, mergeDeep } from './utils';
 
@@ -17,6 +17,7 @@ export function getLayoutConfig(config: ChartCardConfig, hass: HomeAssistant | u
         show: false,
       },
     },
+    colors: DEFAULT_COLORS,
     grid: {
       strokeDashArray: 3,
     },
@@ -63,12 +64,18 @@ export function getLayoutConfig(config: ChartCardConfig, hass: HomeAssistant | u
         return [
           computeName(opts.seriesIndex, conf, undefined, hass2?.states[conf.series[opts.seriesIndex].entity]),
           ' - ',
-          `<strong>${opts.w.globals.series[opts.seriesIndex].slice(-1)}${computeUom(
-            opts.seriesIndex,
-            conf,
-            undefined,
-            hass2?.states[conf.series[opts.seriesIndex].entity],
-          )}</strong>`,
+          `<strong>${
+            opts.w.globals.series[opts.seriesIndex].slice(-1).length !== 0
+              ? opts.w.globals.series[opts.seriesIndex].slice(-1)[0].toFixed(1)
+              : opts.w.globals.series[opts.seriesIndex].slice(-1)
+          }
+            ${computeUom(
+              opts.seriesIndex,
+              conf,
+              undefined,
+              hass2?.states[conf.series[opts.seriesIndex].entity],
+            )}</strong>
+          `,
         ];
       },
     },
diff --git a/src/apexcharts-card.ts b/src/apexcharts-card.ts
index 78ccd68..f3f54a8 100644
--- a/src/apexcharts-card.ts
+++ b/src/apexcharts-card.ts
@@ -13,7 +13,13 @@ import GraphEntry from './graphEntry';
 import { createCheckers } from 'ts-interface-checker';
 import { ChartCardExternalConfig } from './types-config';
 import exportedTypeSuite from './types-config-ti';
-import { DEFAULT_DURATION, DEFAULT_FUNC, DEFAULT_HOURS_TO_SHOW, DEFAULT_SERIE_TYPE } from './const';
+import {
+  DEFAULT_DURATION,
+  DEFAULT_FUNC,
+  DEFAULT_GROUP_BY_FILL,
+  DEFAULT_HOURS_TO_SHOW,
+  DEFAULT_SERIE_TYPE,
+} from './const';
 import parse from 'parse-duration';
 
 /* eslint no-console: 0 */
@@ -122,10 +128,11 @@ class ChartsCard extends LitElement {
         serie.extend_to_end = serie.extend_to_end !== undefined ? serie.extend_to_end : true;
         serie.type = serie.type || DEFAULT_SERIE_TYPE;
         if (!serie.group_by) {
-          serie.group_by = { duration: DEFAULT_DURATION, func: DEFAULT_FUNC };
+          serie.group_by = { duration: DEFAULT_DURATION, func: DEFAULT_FUNC, fill: DEFAULT_GROUP_BY_FILL };
         } else {
           serie.group_by.duration = serie.group_by.duration || DEFAULT_DURATION;
           serie.group_by.func = serie.group_by.func || DEFAULT_FUNC;
+          serie.group_by.fill = serie.group_by.fill || DEFAULT_GROUP_BY_FILL;
         }
         if (!parse(serie.group_by.duration)) {
           throw `Can't parse 'group_by' duration: '${serie.group_by.duration}'`;
diff --git a/src/const.ts b/src/const.ts
index 072738e..d660039 100644
--- a/src/const.ts
+++ b/src/const.ts
@@ -8,3 +8,20 @@ export const DEFAULT_HOURS_TO_SHOW = 24;
 export const DEFAULT_SERIE_TYPE = 'line';
 export const DEFAULT_DURATION = '1h';
 export const DEFAULT_FUNC = 'raw';
+export const DEFAULT_GROUP_BY_FILL = 'last';
+
+export const DEFAULT_COLORS = [
+  'var(--accent-color)',
+  '#3498db',
+  '#e74c3c',
+  '#9b59b6',
+  '#f1c40f',
+  '#2ecc71',
+  '#1abc9c',
+  '#34495e',
+  '#e67e22',
+  '#7f8c8d',
+  '#27ae60',
+  '#2980b9',
+  '#8e44ad',
+];
diff --git a/src/graphEntry.ts b/src/graphEntry.ts
index ecbea68..197a4cb 100644
--- a/src/graphEntry.ts
+++ b/src/graphEntry.ts
@@ -43,6 +43,11 @@ export default class GraphEntry {
   constructor(entity: string, index: number, hoursToShow: number, cache: boolean, config: ChartCardSeriesConfig) {
     const aggregateFuncMap = {
       avg: this._average,
+      max: this._maximum,
+      min: this._minimum,
+      first: this._first,
+      last: this._last,
+      sum: this._sum,
     };
     this._index = index;
     this._cache = cache;
@@ -197,34 +202,100 @@ export default class GraphEntry {
     const ranges = Array.from(this._timeRange.reverseBy('milliseconds', { step: this._groupByDurationMs })).reverse();
     // const res: EntityCachePoints[] = [[]];
     const buckets: HistoryBuckets = [];
-    ranges.forEach((range) => {
-      buckets.push({ timestamp: range.valueOf(), data: [] });
+    ranges.forEach((range, index) => {
+      buckets[index] = { timestamp: range.valueOf(), data: [] };
     });
+    let lastNotNullValue: number | null = null;
     this._history?.data.forEach((entry) => {
-      buckets.forEach((bucket, index) => {
-        if (bucket.timestamp > entry![0] && index > 0) {
-          buckets[index - 1].data.push(entry);
+      let properEntry = entry;
+      // Fill null values
+      if (properEntry[1] === null) {
+        if (this._config.group_by.fill === 'last') {
+          properEntry = [entry[0], lastNotNullValue];
+        } else if (this._config.group_by.fill === 'zero') {
+          properEntry = [entry[0], 0];
         }
+      } else {
+        lastNotNullValue = properEntry[1];
+      }
+
+      buckets.some((bucket, index) => {
+        if (bucket.timestamp > properEntry![0] && index > 0) {
+          buckets[index - 1].data.push(properEntry);
+          return true;
+        }
+        return false;
       });
     });
+    let lastNonNullBucketValue: number | null = null;
+    buckets.forEach((bucket) => {
+      if (bucket.data.length === 0) {
+        if (this._config.group_by.fill === 'last') {
+          bucket.data[0] = [bucket.timestamp, lastNonNullBucketValue];
+        } else if (this._config.group_by.fill === 'zero') {
+          bucket.data[0] = [bucket.timestamp, 0];
+        } else if (this._config.group_by.fill === 'null') {
+          bucket.data[0] = [bucket.timestamp, null];
+        }
+      } else {
+        lastNonNullBucketValue = bucket.data.slice(-1)[0][1];
+      }
+    });
     buckets.pop();
     return buckets;
   }
 
+  private _sum(items: EntityCachePoints): number {
+    if (items.length === 0) return 0;
+    let lastIndex = 0;
+    return items.reduce((sum, entry, index) => {
+      let val = 0;
+      if (entry && entry[1] === null) {
+        val = items[lastIndex][1]!;
+      } else {
+        val = entry[1]!;
+        lastIndex = index;
+      }
+      return sum + val;
+    }, 0);
+  }
+
   private _average(items: EntityCachePoints): number | null {
     if (items.length === 0) return null;
-    let lastIndex = 0;
-    return (
-      items.reduce((sum, entry, index) => {
-        let val = 0;
-        if (entry && entry[1] === null) {
-          val = items[lastIndex]![1]!;
-        } else {
-          val = entry![1]!;
-          lastIndex = index;
-        }
-        return sum + val;
-      }, 0) / items.length
-    );
+    return this._sum(items) / items.length;
+  }
+
+  private _minimum(items: EntityCachePoints): number | null {
+    let min: number | null = null;
+    items.forEach((item) => {
+      if (item[1] !== null)
+        if (min === null) min = item[1];
+        else min = Math.min(item[1], min);
+    });
+    return min;
+  }
+
+  private _maximum(items: EntityCachePoints): number | null {
+    let max: number | null = null;
+    items.forEach((item) => {
+      if (item[1] !== null)
+        if (max === null) max = item[1];
+        else max = Math.max(item[1], max);
+    });
+    return max;
+  }
+
+  private _last(items: EntityCachePoints): number | null {
+    if (items.length === 0) return null;
+    return items.slice(-1)[0][1];
+  }
+
+  private _first(items: EntityCachePoints): number | null {
+    if (items.length === 0) return null;
+    return items[0][1];
+  }
+
+  private _filterNulls(items: EntityCachePoints): EntityCachePoints {
+    return items.filter((item) => item[1] !== null);
   }
 }
diff --git a/src/types-config-ti.ts b/src/types-config-ti.ts
index d915e81..78c7712 100644
--- a/src/types-config-ti.ts
+++ b/src/types-config-ti.ts
@@ -28,10 +28,13 @@ export const ChartCardSeriesExternalConfig = t.iface([], {
   "group_by": t.opt(t.iface([], {
     "duration": t.opt("string"),
     "func": t.opt("GroupByFunc"),
+    "fill": t.opt("GroupByFill"),
   })),
 });
 
-export const GroupByFunc = t.union(t.lit('raw'), t.lit('avg'));
+export const GroupByFill = t.union(t.lit('null'), t.lit('last'), t.lit('zero'));
+
+export const GroupByFunc = t.union(t.lit('raw'), t.lit('avg'), t.lit('min'), t.lit('max'), t.lit('last'), t.lit('first'), t.lit('sum'));
 
 export const ChartCardHeaderExternalConfig = t.iface([], {
   "show": t.opt("boolean"),
@@ -41,6 +44,7 @@ export const ChartCardHeaderExternalConfig = t.iface([], {
 const exportedTypeSuite: t.ITypeSuite = {
   ChartCardExternalConfig,
   ChartCardSeriesExternalConfig,
+  GroupByFill,
   GroupByFunc,
   ChartCardHeaderExternalConfig,
 };
diff --git a/src/types-config.ts b/src/types-config.ts
index 0bd0ace..9d49137 100644
--- a/src/types-config.ts
+++ b/src/types-config.ts
@@ -23,10 +23,13 @@ export interface ChartCardSeriesExternalConfig {
   group_by?: {
     duration?: string;
     func?: GroupByFunc;
+    fill?: GroupByFill;
   };
 }
 
-export type GroupByFunc = 'raw' | 'avg';
+export type GroupByFill = 'null' | 'last' | 'zero';
+
+export type GroupByFunc = 'raw' | 'avg' | 'min' | 'max' | 'last' | 'first' | 'sum';
 
 export interface ChartCardHeaderExternalConfig {
   show?: boolean;
diff --git a/src/types.ts b/src/types.ts
index 1e6a984..e0d6b5d 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,5 +1,5 @@
 import { ApexOptions } from 'apexcharts';
-import { ChartCardExternalConfig, ChartCardSeriesExternalConfig, GroupByFunc } from './types-config';
+import { ChartCardExternalConfig, ChartCardSeriesExternalConfig, GroupByFill, GroupByFunc } from './types-config';
 
 export interface ChartCardConfig extends ChartCardExternalConfig {
   series: ChartCardSeriesConfig[];
@@ -14,6 +14,7 @@ export interface ChartCardSeriesConfig extends ChartCardSeriesExternalConfig {
   group_by: {
     duration: string;
     func: GroupByFunc;
+    fill: GroupByFill;
   };
 }
 
@@ -23,7 +24,7 @@ export interface EntityEntryCache {
   data: EntityCachePoints;
 }
 
-export type EntityCachePoints = Array<[number, number | null] | undefined>;
+export type EntityCachePoints = Array<[number, number | null]>;
 
 export type HassHistory = Array<[HassHistoryEntry] | undefined>;