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Comparing Date Periods

Compare your analytics to the previous period to measure growth, spot trends, and evaluate performance. A detailed Zenovay analytics guide.

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Period comparison helps you see how your metrics change over time. Zenovay automatically compares the period you're viewing against the period immediately before it, so you can measure growth and catch sudden shifts at a glance.

How comparison works

Open your website's dashboard and select the Analytics tab. Pick a time window from the period selector in the header (Today, Yesterday, Last 7 / 14 / 30 / 90 days, and longer windows depending on your plan). Two things update automatically:

  • Metric deltas appear next to the headline numbers (Visitors, Bounce rate, Avg duration). Each delta shows the percentage change versus the same-length period right before your selection.
  • The visitors chart draws a dashed line for the previous period behind the solid current-period area, so you can see the shape of the change, not just the totals.

There's no separate "enable comparison" step for the metric deltas, they're always on whenever a previous period exists.

The "vs previous" chart overlay

The visitors chart has a vs previous toggle in its header. It's on by default and draws the dashed previous-period line described above. Turn it off if you want a cleaner view of just the current period, and back on to bring the comparison back.

  1. Open the Analytics tab

    Go to your website's dashboard and select Analytics.

  2. Choose a period

    Use the period selector in the header to pick the window you want to analyze.

  3. Toggle the comparison line

    Use the vs previous button above the chart to show or hide the dashed previous-period line.

What the previous period is

Zenovay mirrors your selected window backwards by the same length:

  • Last 7 days vs the 7 days before that
  • Last 30 days vs the 30 days before that
  • A custom range vs the equal-length range immediately before it

This makes "this period vs the last comparable period" the default lens. Comparison is unavailable for All time (there's no earlier period to compare against), and it's bounded by your plan's data retention, so a comparison period that falls outside your retention window won't return data.

Reading comparison data

Metric deltas

Each headline metric shows:

  • Current value: the result for the period you selected
  • Delta pill: the percentage change versus the previous period (with an up or down arrow)

Bounce rate is inverted: a decrease is treated as an improvement, so a falling bounce rate reads as positive.

Chart overlay

On the visitors chart:

  • Solid area: the current period
  • Dashed line: the previous period
  • Hover: the tooltip shows both the current and previous value for that point

Color indicators

ColorMeaning
GreenA change in the favorable direction
RedA change in the unfavorable direction

Context matters. A red delta on bounce rate is actually good, because Zenovay treats a falling bounce rate as an improvement. Always read each metric on its own terms.

Percentage change calculation

Formula

% Change = ((New Value - Old Value) / Old Value) × 100

Examples

CurrentPreviousChange% Change
1,000800+200+25%
1,0001,200-200-16.7%
1,0001,00000%

Special cases

  • Previous = 0: a percentage change can't be calculated against a zero baseline
  • Both = 0: there's nothing to compare
  • Very small base values: small absolute moves can show as large percentages

Metric-specific reading

Visitors

  • Growth indicates expanding reach
  • A decline may signal an issue or seasonality
  • Cross-check the source breakdown to see where the change came from

Bounce rate

  • Lower is usually better (and is treated as the favorable direction)
  • Small changes may not be significant
  • Read it alongside traffic volume

Session duration

  • Higher often means deeper engagement
  • Context matters (a quick answer found vs. a long read)
  • Compare across traffic sources

Interpreting results

Signal vs noise

Consider how much data you have:

  • Large sample: small changes can still be meaningful
  • Small sample: large percentage swings may just be noise

External factors

Account for things outside your dashboard:

  • Seasonality and holidays
  • News events
  • Marketing activity
  • Site or tracking changes

Correlation vs causation

A change might not mean what you think:

  • A traffic spike could be bots
  • A bounce-rate drop could follow a tracking change
  • Investigate before concluding

Comparison best practices

Apples to apples

Keep comparisons fair:

  • The previous period already matches your selected length day-for-day
  • Watch for a holiday that lands in only one of the two periods
  • Consider your business cycle

Note the context

When you share a number, note what was happening:

  • Campaigns running
  • Site changes made
  • External events

Establish a cadence

A simple routine keeps you honest:

FrequencyWhat you're looking at
DailyToday vs yesterday
WeeklyLast 7 days vs the prior 7
MonthlyLast 30 days vs the prior 30

Troubleshooting

No comparison data

If deltas or the dashed line don't appear:

  • Make sure you're not on the All time window (it has no previous period)
  • Check that data exists for the previous period
  • Confirm the previous period is within your plan's retention window

Percentages look wrong

If a percentage seems off:

  • A very small base number can produce a large percentage
  • Confirm both periods actually have data
  • Remember bounce rate is read as "down is good"

Chart shows only one line

If the dashed previous-period line is missing:

  • Check that the vs previous toggle is on
  • The previous period may have no data for that window

Reporting with comparisons

Use period-over-period numbers in your updates: the headline metric, its delta, and a one-line explanation of any external factor. On the Scale plan you can also schedule recurring reports so these summaries land in your inbox automatically.

Next steps

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