eviceFirstLastBooking').textContent = `${firstBooking} - ${lastBooking}`;

            // Update revenue chart
            updateDeviceRevenueChart(data.monthlyRevenue);

            // Update customer bookings table
            updateCustomerBookingsTable(data.customerBookings);
        }

        function updateDeviceRevenueChart(monthlyData) {
            const ctx = document.getElementById('deviceRevenueChart').getContext('2d');
            
            // Destroy existing chart
            if (deviceRe