diff --git a/stats/chartitem.cpp b/stats/chartitem.cpp
index 77fc0eac4..034733188 100644
--- a/stats/chartitem.cpp
+++ b/stats/chartitem.cpp
@@ -19,7 +19,7 @@ static int round_up(double f)
 	return static_cast<int>(ceil(f));
 }
 
-ChartItem::ChartItem(StatsView &v, ChartZValue z) :
+ChartItem::ChartItem(StatsView &v, size_t z) :
 	dirty(false), prev(nullptr), next(nullptr),
 	zValue(z), view(v)
 {
@@ -42,7 +42,7 @@ void ChartItem::markDirty()
 	view.registerDirtyChartItem(*this);
 }
 
-ChartPixmapItem::ChartPixmapItem(StatsView &v, ChartZValue z) : HideableChartItem(v, z),
+ChartPixmapItem::ChartPixmapItem(StatsView &v, size_t z) : HideableChartItem(v, z),
 	positionDirty(false), textureDirty(false)
 {
 }
@@ -111,7 +111,7 @@ QRectF ChartPixmapItem::getRect() const
 static const int scatterItemDiameter = 10;
 static const int scatterItemBorder = 1;
 
-ChartScatterItem::ChartScatterItem(StatsView &v, ChartZValue z, const StatsTheme &theme, bool selected) : HideableChartItem(v, z),
+ChartScatterItem::ChartScatterItem(StatsView &v, size_t z, const StatsTheme &theme, bool selected) : HideableChartItem(v, z),
 	theme(theme),
 	positionDirty(false), textureDirty(false),
 	highlight(selected ? Highlight::Selected : Highlight::Unselected)
@@ -214,7 +214,7 @@ QRectF ChartScatterItem::getRect() const
 	return rect;
 }
 
-ChartRectItem::ChartRectItem(StatsView &v, ChartZValue z,
+ChartRectItem::ChartRectItem(StatsView &v, size_t z,
 			     const QPen &pen, const QBrush &brush, double radius) : ChartPixmapItem(v, z),
 	pen(pen), brush(brush), radius(radius)
 {
@@ -236,7 +236,7 @@ void ChartRectItem::resize(QSizeF size)
 	painter->drawRoundedRect(rect, radius, radius, Qt::AbsoluteSize);
 }
 
-ChartTextItem::ChartTextItem(StatsView &v, ChartZValue z, const QFont &f, const std::vector<QString> &text, bool center) :
+ChartTextItem::ChartTextItem(StatsView &v, size_t z, const QFont &f, const std::vector<QString> &text, bool center) :
 	ChartPixmapItem(v, z), f(f), center(center)
 {
 	QFontMetrics fm(f);
@@ -254,7 +254,7 @@ ChartTextItem::ChartTextItem(StatsView &v, ChartZValue z, const QFont &f, const
 	resize(QSizeF(totalWidth, totalHeight));
 }
 
-ChartTextItem::ChartTextItem(StatsView &v, ChartZValue z, const QFont &f, const QString &text) :
+ChartTextItem::ChartTextItem(StatsView &v, size_t z, const QFont &f, const QString &text) :
 	ChartTextItem(v, z, f, std::vector<QString>({ text }), true)
 {
 }
@@ -280,7 +280,7 @@ void ChartTextItem::setColor(const QColor &c, const QColor &background)
 	setTextureDirty();
 }
 
-ChartPieItem::ChartPieItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth) : ChartPixmapItem(v, z),
+ChartPieItem::ChartPieItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth) : ChartPixmapItem(v, z),
 	theme(theme),
 	borderWidth(borderWidth)
 {
@@ -322,7 +322,7 @@ void ChartPieItem::resize(QSizeF size)
 	img->fill(Qt::transparent);
 }
 
-ChartLineItemBase::ChartLineItemBase(StatsView &v, ChartZValue z, QColor color, double width) : HideableChartItem(v, z),
+ChartLineItemBase::ChartLineItemBase(StatsView &v, size_t z, QColor color, double width) : HideableChartItem(v, z),
 	color(color), width(width), positionDirty(false), materialDirty(false)
 {
 }
@@ -416,7 +416,7 @@ void ChartRectLineItem::render()
 	positionDirty = materialDirty = false;
 }
 
-ChartBarItem::ChartBarItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth) : HideableChartItem(v, z),
+ChartBarItem::ChartBarItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth) : HideableChartItem(v, z),
 	theme(theme),
 	borderWidth(borderWidth), selected(false),
 	positionDirty(false), colorDirty(false), selectedDirty(false)
@@ -548,7 +548,7 @@ QRectF ChartBarItem::getRect() const
 	return rect;
 }
 
-ChartBoxItem::ChartBoxItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth) :
+ChartBoxItem::ChartBoxItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth) :
 	ChartBarItem(v, z, theme, borderWidth)
 {
 }
diff --git a/stats/chartitem.h b/stats/chartitem.h
index 7baea1fe9..0e68fc920 100644
--- a/stats/chartitem.h
+++ b/stats/chartitem.h
@@ -18,7 +18,6 @@ class QSGTexture;
 class QSGTextureMaterial;
 class StatsTheme;
 class StatsView;
-enum class ChartZValue : int;
 
 class ChartItem {
 public:
@@ -26,10 +25,10 @@ public:
 	virtual void render() = 0;
 	bool dirty;				// If true, call render() when rebuilding the scene
 	ChartItem *prev, *next;			// Double linked list of items
-	const ChartZValue zValue;
+	const size_t zValue;
 	virtual ~ChartItem();			// Attention: must only be called by render thread.
 protected:
-	ChartItem(StatsView &v, ChartZValue z);
+	ChartItem(StatsView &v, size_t z);
 	QSizeF sceneSize() const;
 	StatsView &view;
 	void markDirty();
@@ -38,7 +37,7 @@ protected:
 template <typename Node>
 class HideableChartItem : public ChartItem {
 protected:
-	HideableChartItem(StatsView &v, ChartZValue z);
+	HideableChartItem(StatsView &v, size_t z);
 	std::unique_ptr<Node> node;
 	bool visible;
 	bool visibleChanged;
@@ -56,7 +55,7 @@ using HideableChartProxyItem = HideableChartItem<HideableQSGNode<QSGProxyNode<No
 // A chart item that blits a precalculated pixmap onto the scene.
 class ChartPixmapItem : public HideableChartProxyItem<QSGImageNode> {
 public:
-	ChartPixmapItem(StatsView &v, ChartZValue z);
+	ChartPixmapItem(StatsView &v, size_t z);
 	~ChartPixmapItem();
 
 	void setPos(QPointF pos);
@@ -78,7 +77,7 @@ private:
 // Draw a rectangular background after resize. Children are responsible for calling update().
 class ChartRectItem : public ChartPixmapItem {
 public:
-	ChartRectItem(StatsView &v, ChartZValue z, const QPen &pen, const QBrush &brush, double radius);
+	ChartRectItem(StatsView &v, size_t z, const QPen &pen, const QBrush &brush, double radius);
 	~ChartRectItem();
 	void resize(QSizeF size);
 private:
@@ -90,8 +89,8 @@ private:
 // Attention: text is only drawn after calling setColor()!
 class ChartTextItem : public ChartPixmapItem {
 public:
-	ChartTextItem(StatsView &v, ChartZValue z, const QFont &f, const std::vector<QString> &text, bool center);
-	ChartTextItem(StatsView &v, ChartZValue z, const QFont &f, const QString &text);
+	ChartTextItem(StatsView &v, size_t z, const QFont &f, const std::vector<QString> &text, bool center);
+	ChartTextItem(StatsView &v, size_t z, const QFont &f, const QString &text);
 	void setColor(const QColor &color); // Draw on transparent background
 	void setColor(const QColor &color, const QColor &background); // Fill rectangle with given background color
 private:
@@ -108,7 +107,7 @@ private:
 // A pie chart item: draws disk segments onto a pixmap.
 class ChartPieItem : public ChartPixmapItem {
 public:
-	ChartPieItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth);
+	ChartPieItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth);
 	void drawSegment(double from, double to, QColor fill, QColor border, bool selected); // from and to are relative (0-1 is full disk).
 	void resize(QSizeF size);	// As in base class, but clears the canvas
 private:
@@ -119,7 +118,7 @@ private:
 // Common data for line and rect items. Both are represented by two points.
 class ChartLineItemBase : public HideableChartItem<HideableQSGNode<QSGGeometryNode>> {
 public:
-	ChartLineItemBase(StatsView &v, ChartZValue z, QColor color, double width);
+	ChartLineItemBase(StatsView &v, size_t z, QColor color, double width);
 	~ChartLineItemBase();
 	void setLine(QPointF from, QPointF to);
 protected:
@@ -148,7 +147,7 @@ public:
 // A bar in a bar chart: a rectangle bordered by lines.
 class ChartBarItem : public HideableChartProxyItem<QSGRectangleNode> {
 public:
-	ChartBarItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth);
+	ChartBarItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth);
 	~ChartBarItem();
 	void setColor(QColor color, QColor borderColor);
 	void setRect(const QRectF &rect);
@@ -178,7 +177,7 @@ private:
 // A box-and-whiskers item. This is a bit lazy: derive from the bar item and add whiskers.
 class ChartBoxItem : public ChartBarItem {
 public:
-	ChartBoxItem(StatsView &v, ChartZValue z, const StatsTheme &theme, double borderWidth);
+	ChartBoxItem(StatsView &v, size_t z, const StatsTheme &theme, double borderWidth);
 	~ChartBoxItem();
 	void setBox(const QRectF &rect, double min, double max, double median); // The rect describes Q1, Q3.
 	QRectF getRect() const;		// Note: this extends the center rectangle to include the whiskers.
@@ -196,7 +195,7 @@ private:
 // scatter item here, but so it is for now.
 class ChartScatterItem : public HideableChartProxyItem<QSGImageNode> {
 public:
-	ChartScatterItem(StatsView &v, ChartZValue z, const StatsTheme &theme, bool selected);
+	ChartScatterItem(StatsView &v, size_t z, const StatsTheme &theme, bool selected);
 	~ChartScatterItem();
 
 	// Currently, there is no highlighted and selected status.
@@ -240,7 +239,7 @@ void HideableChartItem<Node>::createNode(Args&&... args)
 }
 
 template <typename Node>
-HideableChartItem<Node>::HideableChartItem(StatsView &v, ChartZValue z) : ChartItem(v, z),
+HideableChartItem<Node>::HideableChartItem(StatsView &v, size_t z) : ChartItem(v, z),
 	visible(true), visibleChanged(false)
 {
 }
diff --git a/stats/statsview.cpp b/stats/statsview.cpp
index 130f3895a..1fd7866e7 100644
--- a/stats/statsview.cpp
+++ b/stats/statsview.cpp
@@ -21,7 +21,6 @@
 #include "core/selection.h"
 #include "core/trip.h"
 
-#include <array> // for std::array
 #include <cmath>
 #include <QQuickItem>
 #include <QQuickWindow>
@@ -35,6 +34,7 @@ static const double titleBorder = 2.0;			// Border between title and chart
 static const double selectionLassoWidth = 2.0;		// Border between title and chart
 
 StatsView::StatsView(QQuickItem *parent) : QQuickItem(parent),
+	maxZ(ChartZValue::Count),
 	backgroundDirty(true),
 	currentTheme(&getStatsTheme(false)),
 	backgroundColor(currentTheme->backgroundColor),
@@ -129,16 +129,18 @@ using ZNode = HideableQSGNode<QSGNode>;
 class RootNode : public QSGNode
 {
 public:
-	RootNode(StatsView &view, QColor backgroundColor);
+	RootNode(StatsView &view, QColor backgroundColor, size_t maxZ);
 	~RootNode();
 	StatsView &view;
 	std::unique_ptr<QSGRectangleNode> backgroundNode; // solid background
 	// We entertain one node per Z-level.
-	std::array<std::unique_ptr<ZNode>, (size_t)ChartZValue::Count> zNodes;
+	std::vector<std::unique_ptr<ZNode>> zNodes;
 };
 
-RootNode::RootNode(StatsView &view, QColor backgroundColor) : view(view)
+RootNode::RootNode(StatsView &view, QColor backgroundColor, size_t maxZ) : view(view)
 {
+	zNodes.resize(maxZ);
+
 	// Add a background rectangle with a solid color. This could
 	// also be done on the widget level, but would have to be done
 	// separately for desktop and mobile, so do it here.
@@ -172,7 +174,7 @@ QSGNode *StatsView::updatePaintNode(QSGNode *oldNode, QQuickItem::UpdatePaintNod
 	// This is just a copy of what is found in Qt's documentation.
 	RootNode *n = static_cast<RootNode *>(oldNode);
 	if (!n)
-		n = rootNode = new RootNode(*this, backgroundColor);
+		n = rootNode = new RootNode(*this, backgroundColor, maxZ);
 
 	// Delete all chart items that are marked for deletion.
 	freeDeletedChartItems();
@@ -217,9 +219,9 @@ void StatsView::emergencyShutdown()
 	rootNode = nullptr;
 }
 
-void StatsView::addQSGNode(QSGNode *node, ChartZValue z)
+void StatsView::addQSGNode(QSGNode *node, size_t z)
 {
-	int idx = std::clamp((int)z, 0, (int)ChartZValue::Count - 1);
+	size_t idx = std::clamp(z, (size_t)0, maxZ);
 	rootNode->zNodes[idx]->appendChildNode(node);
 }
 
@@ -617,7 +619,7 @@ void StatsView::updateFeatures()
 
 	// For labels, we are brutal: simply show/hide the whole z-level with the labels
 	if (rootNode)
-		rootNode->zNodes[(int)ChartZValue::SeriesLabels]->setVisible(state.labels);
+		rootNode->zNodes[ChartZValue::SeriesLabels]->setVisible(state.labels);
 
 	if (meanMarker)
 		meanMarker->setVisible(state.mean);
diff --git a/stats/statsview.h b/stats/statsview.h
index a0a44bc89..a51bf9a53 100644
--- a/stats/statsview.h
+++ b/stats/statsview.h
@@ -34,7 +34,6 @@ class QSGTexture;
 class RootNode;	// Internal implementation detail
 
 enum class ChartSubType : int;
-enum class ChartZValue : int;
 enum class StatsOperation : int;
 enum class ChartSortMode : int;
 
@@ -56,7 +55,7 @@ public:
 	void setBackgroundColor(QColor color);		// Chart must be replot for color to become effective.
 	void setTheme(bool dark);			// Chart must be replot for theme to become effective.
 	const StatsTheme &getCurrentTheme() const;
-	void addQSGNode(QSGNode *node, ChartZValue z);	// Must only be called in render thread!
+	void addQSGNode(QSGNode *node, size_t z);	// Must only be called in render thread!
 	void registerChartItem(ChartItem &item);
 	void registerDirtyChartItem(ChartItem &item);
 	void emergencyShutdown();			// Called when QQuick decides to delete our root node.
@@ -76,6 +75,7 @@ private slots:
 	void divesSelected(const QVector<dive *> &dives);
 private:
 	// QtQuick related things
+	size_t maxZ;
 	bool backgroundDirty;
 	QRectF plotRect;
 	QSGNode *updatePaintNode(QSGNode *oldNode, QQuickItem::UpdatePaintNodeData *updatePaintNodeData) override;
diff --git a/stats/zvalues.h b/stats/zvalues.h
index dc84bdd99..39e0526a5 100644
--- a/stats/zvalues.h
+++ b/stats/zvalues.h
@@ -5,16 +5,21 @@
 // drawn in order of addition to the scene.
 #ifndef ZVALUES_H
 
-enum class ChartZValue {
-	Grid = 0,
-	Series,
-	Axes,
-	SeriesLabels,
-	ChartFeatures,	// quartile markers and regression lines
-	Selection,
-	InformationBox,
-	Legend,
-	Count
+// Encapsulating an enum in a struct is stupid, but allows us
+// to not poison the namespace and yet autoconvert to int
+// (in constrast to enum class). enum is so broken!
+struct ChartZValue {
+	enum ZValues {
+		Grid = 0,
+		Series,
+		Axes,
+		SeriesLabels,
+		ChartFeatures,	// quartile markers and regression lines
+		Selection,
+		InformationBox,
+		Legend,
+		Count
+	};
 };
 
 #endif