Recorded price history USD Listing start period All years 5 years 1 year
Recorded US-dollar price history Logarithmic price scale (price + 1). Horizontal axis: listing start date. Vertical axis: recorded price in US dollars. Filled dots have recorded sales; open dots have no recorded sales. The oxide step line shows calendar-month medians, with gaps for missing months. 0 1 10 100 1000 10000 Mar 2023 Jan 2024 Dec 2024 Nov 2025 Oct 2026 2023-03-22: US$13500.00; no sale recorded 2023-03-25: US$13499.80; no sale recorded 2023-03-25: US$13499.90; no sale recorded 2023-03-25: US$13499.10; no sale recorded 2023-03-25: US$13499.20; no sale recorded 2023-03-25: US$13499.30; no sale recorded 2023-03-27: US$13499.00; no sale recorded 2023-03-27: US$13499.40; no sale recorded 2023-05-16: US$13500.00; no sale recorded 2023-05-16: US$5922.00; no sale recorded 2023-06-12: US$13400.00; no sale recorded 2023-06-24: US$13499.00; no sale recorded 2023-06-24: US$13499.80; no sale recorded 2023-06-24: US$13499.10; no sale recorded 2023-06-24: US$13499.90; no sale recorded 2023-06-24: US$13499.40; no sale recorded 2023-06-24: US$13499.50; no sale recorded 2023-06-24: US$13499.30; no sale recorded 2023-08-02: US$5500.00; no sale recorded 2023-08-19: US$5499.50; no sale recorded 2023-08-19: US$5499.20; no sale recorded 2023-08-19: US$5498.50; no sale recorded 2023-08-21: US$13499.90; no sale recorded 2023-08-21: US$13499.30; no sale recorded 2023-08-21: US$13499.50; no sale recorded 2023-08-21: US$13499.00; no sale recorded 2023-08-21: US$13499.80; no sale recorded 2023-09-04: US$13151.87; no sale recorded 2023-09-27: US$13497.38; no sale recorded 2024-01-14: US$13499.40; no sale recorded 2024-01-14: US$13499.60; no sale recorded 2024-01-14: US$13499.50; no sale recorded 2024-01-14: US$6996.00; no sale recorded 2024-01-14: US$6998.00; no sale recorded 2024-01-14: US$6997.00; no sale recorded 2024-01-14: US$13499.10; no sale recorded 2024-01-18: US$7300.00; no sale recorded 2024-01-25: US$7600.00; no sale recorded 2024-02-05: US$11199.99; no sale recorded 2024-05-27: US$3500.00; no sale recorded 2024-05-31: US$6995.00; no sale recorded 2024-05-31: US$6996.00; no sale recorded 2024-05-31: US$6997.00; no sale recorded 2024-06-14: US$6997.00; no sale recorded 2024-06-14: US$6996.00; no sale recorded 2024-06-21: US$3901.00; no sale recorded 2024-06-27: US$6499.00; no sale recorded 2024-08-12: US$4228.80; no sale recorded 2024-08-12: US$4169.80; no sale recorded 2024-08-15: US$5849.10; sold recorded 2024-08-18: US$5790.61; no sale recorded 2024-09-03: US$6200.00; no sale recorded 2024-09-06: US$6233.51; no sale recorded 2024-09-30: US$6200.00; no sale recorded 2024-09-30: US$6997.00; sold recorded 2024-11-13: US$6200.00; sold recorded 2024-11-13: US$45.00; no sale recorded 2024-12-25: US$6998.00; sold recorded 2025-01-17: US$6595.74; no sale recorded 2025-01-18: US$6200.00; sold recorded 2025-01-31: US$6203.00; sold recorded 2025-02-10: US$6200.02; no sale recorded 2025-02-12: US$7350.00; no sale recorded 2025-02-12: US$6200.07; sold recorded 2025-02-14: US$6888.89; sold recorded 2025-02-20: US$21384.00; no sale recorded 2025-03-03: US$6200.50; no sale recorded 2025-03-03: US$7294.12; sold recorded 2025-03-05: US$6998.00; no sale recorded 2025-03-06: US$6199.99; no sale recorded 2025-03-10: US$4081.30; no sale recorded 2025-03-15: US$3484.00; no sale recorded 2025-03-15: US$3488.00; no sale recorded 2025-03-17: US$6998.00; no sale recorded 2025-03-19: US$6383.44; sold recorded 2025-03-19: US$11500.00; no sale recorded 2025-03-19: US$8643.00; no sale recorded 2025-03-31: US$6739.13; sold recorded 2025-03-31: US$6888.89; sold recorded 2025-04-01: US$6805.88; no sale recorded 2025-04-03: US$6200.09; no sale recorded 2025-04-10: US$6200.88; sold recorded 2025-04-14: US$3487.00; no sale recorded 2025-05-24: US$7300.76; no sale recorded 2025-06-12: US$4255.36; no sale recorded 2025-06-13: US$7000.00; no sale recorded 2025-06-19: US$7000.00; no sale recorded 2025-07-01: US$6595.74; no sale recorded 2025-07-02: US$6989.10; no sale recorded 2025-07-03: US$6200.00; no sale recorded 2025-07-08: US$8737.00; no sale recorded 2025-07-11: US$6999.00; no sale recorded 2025-07-18: US$8174.79; no sale recorded 2025-07-21: US$4291.47; no sale recorded 2025-07-21: US$7126.33; no sale recorded 2025-07-22: US$12827.39; no sale recorded 2025-07-24: US$6996.00; no sale recorded 2025-07-28: US$6999.00; no sale recorded 2025-08-01: US$6979.00; no sale recorded 2025-08-04: US$6999.00; no sale recorded 2025-08-05: US$3481.00; no sale recorded 2025-08-11: US$13327.98; no sale recorded 2025-08-12: US$7000.00; no sale recorded 2025-08-13: US$3490.00; no sale recorded 2025-08-14: US$3485.00; no sale recorded 2025-08-14: US$6862.33; no sale recorded 2025-08-14: US$8260.00; no sale recorded 2025-08-14: US$3485.00; no sale recorded 2025-08-15: US$6990.00; no sale recorded 2025-08-18: US$6208.94; no sale recorded 2025-08-18: US$6194.98; no sale recorded 2025-08-20: US$8394.00; no sale recorded 2025-08-22: US$6201.90; no sale recorded 2025-08-25: US$7021.00; no sale recorded 2025-08-28: US$6999.00; no sale recorded 2025-08-28: US$6999.00; no sale recorded 2025-09-01: US$3488.00; no sale recorded 2025-09-01: US$3487.00; no sale recorded 2025-09-09: US$6852.33; no sale recorded 2025-09-09: US$8999.85; no sale recorded 2025-09-09: US$8999.82; no sale recorded 2025-09-09: US$8999.00; no sale recorded 2025-09-10: US$4322.64; no sale recorded 2025-09-12: US$11185.00; no sale recorded 2025-09-16: US$6198.95; no sale recorded 2025-10-01: US$6199.90; no sale recorded 2025-10-05: US$3500.00; no sale recorded 2025-10-08: US$11186.00; no sale recorded 2025-10-09: US$6200.99; no sale recorded 2025-10-13: US$6326.53; no sale recorded 2025-10-22: US$5779.54; no sale recorded 2025-10-22: US$6190.00; no sale recorded 2025-10-27: US$6204.49; no sale recorded 2025-10-29: US$5571.91; no sale recorded 2025-11-01: US$7541.29; no sale recorded 2025-11-04: US$6007.39; no sale recorded 2025-11-06: US$6190.00; no sale recorded 2025-11-12: US$6212.68; no sale recorded 2025-11-12: US$5293.31; no sale recorded 2025-11-12: US$6250.00; no sale recorded 2025-11-12: US$6190.00; no sale recorded 2025-11-13: US$6200.02; no sale recorded 2025-11-17: US$8242.30; no sale recorded 2025-11-17: US$7569.77; no sale recorded 2025-11-19: US$9696.95; no sale recorded 2025-11-24: US$6200.99; no sale recorded 2025-11-25: US$6215.00; no sale recorded 2025-11-26: US$6200.96; no sale recorded 2025-11-27: US$6180.00; no sale recorded 2025-11-27: US$6180.00; no sale recorded 2025-11-28: US$8537.40; no sale recorded 2025-12-02: US$6200.10; no sale recorded 2025-12-03: US$6200.10; no sale recorded 2025-12-08: US$6200.10; no sale recorded 2025-12-08: US$6200.02; no sale recorded 2025-12-10: US$6199.90; no sale recorded 2025-12-12: US$6195.00; no sale recorded 2025-12-15: US$6190.00; no sale recorded 2025-12-17: US$6486.50; no sale recorded 2025-12-17: US$6195.00; no sale recorded 2025-12-18: US$6190.00; no sale recorded 2025-12-22: US$6966.29; no sale recorded 2025-12-24: US$6179.09; no sale recorded 2025-12-29: US$7908.87; no sale recorded 2025-12-30: US$6998.95; no sale recorded 2025-12-30: US$6999.00; no sale recorded 2026-01-06: US$6299.00; no sale recorded 2026-01-06: US$6195.00; no sale recorded 2026-01-14: US$6391.75; no sale recorded 2026-01-19: US$6235.00; no sale recorded 2026-01-20: US$6199.34; no sale recorded 2026-01-29: US$6666.67; no sale recorded 2026-02-27: US$6411.84; no sale recorded 2026-03-03: US$6407.75; no sale recorded 2026-03-10: US$7000.00; no sale recorded 2026-03-11: US$6819.89; no sale recorded 2026-03-12: US$8318.10; no sale recorded 2026-03-13: US$6294.00; no sale recorded 2026-03-13: US$6295.00; no sale recorded 2026-03-14: US$6995.00; no sale recorded 2026-03-17: US$6375.24; no sale recorded 2026-03-17: US$6399.75; no sale recorded 2026-03-22: US$4726.00; no sale recorded 2026-04-09: US$7000.00; no sale recorded 2026-04-10: US$6995.99; no sale recorded 2026-04-17: US$7519.71; no sale recorded 2026-04-22: US$7101.94; no sale recorded 2026-05-04: US$6412.75; no sale recorded 2026-05-05: US$6377.76; no sale recorded 2026-05-08: US$6390.95; no sale recorded 2026-05-21: US$6381.75; no sale recorded 2026-05-25: US$6376.87; no sale recorded 2026-05-27: US$6402.85; no sale recorded 2026-05-27: US$6419.25; no sale recorded 2026-05-28: US$6441.31; no sale recorded 2026-06-01: US$6441.36; no sale recorded 2026-06-02: US$7143.68; no sale recorded 2026-06-04: US$6113.00; no sale recorded 2026-06-04: US$6483.21; no sale recorded 2026-06-05: US$6113.00; no sale recorded 2026-06-05: US$6599.00; no sale recorded 2026-06-05: US$7694.48; no sale recorded 2026-06-05: US$6462.76; no sale recorded 2026-06-05: US$6441.36; no sale recorded 2026-06-10: US$6868.41; no sale recorded 2026-06-11: US$6459.30; no sale recorded 2026-06-18: US$6456.09; no sale recorded 2026-06-18: US$6446.31; no sale recorded 2026-06-20: US$8155.20; no sale recorded 2026-06-24: US$6461.31; no sale recorded 2026-06-25: US$6451.31; no sale recorded 2026-07-07: US$7501.32; no sale recorded 2026-07-09: US$8150.40; no sale recorded 2026-07-10: US$7353.42; no sale recorded 2026-07-13: US$6796.00; no sale recorded 2026-07-13: US$6798.00; no sale recorded 2026-07-14: US$8089.62; no sale recorded 2026-07-15: US$6995.75; no sale recorded 2026-07-15: US$6985.53; no sale recorded 2026-07-21: US$6986.74; no sale recorded 2026-07-31: US$6986.74; no sale recorded 2026-08-04: US$5124.90; no sale recorded 2026-08-05: US$6970.84; no sale recorded 2026-08-10: US$6971.70; no sale recorded 2026-08-11: US$6970.76; no sale recorded 2026-08-31: US$7003.25; no sale recorded 2026-09-03: US$7005.15; no sale recorded 2026-09-09: US$6970.75; no sale recorded 2026-09-14: US$7511.56; no sale recorded 2026-09-21: US$6991.30; no sale recorded 2026-09-21: US$6970.75; no sale recorded 2026-09-23: US$995.71; no sale recorded 2026-10-07: US$6970.85; no sale recorded 2026-10-19: US$7007.40; no sale recorded 2026-10-23: US$6967.76; no sale recorded Recorded US-dollar price history Logarithmic price scale (price + 1). Horizontal axis: listing start date. Vertical axis: recorded price in US dollars. Filled dots have recorded sales; open dots have no recorded sales. The oxide step line shows calendar-month medians, with gaps for missing months. 0 1 10 100 1000 10000 Mar 2023 Dec 2024 Oct 2026 2023-03-22: US$13500.00; no sale recorded 2023-03-25: US$13499.80; no sale recorded 2023-03-25: US$13499.90; no sale recorded 2023-03-25: US$13499.10; no sale recorded 2023-03-25: US$13499.20; no sale recorded 2023-03-25: US$13499.30; no sale recorded 2023-03-27: US$13499.00; no sale recorded 2023-03-27: US$13499.40; no sale recorded 2023-05-16: US$13500.00; no sale recorded 2023-05-16: US$5922.00; no sale recorded 2023-06-12: US$13400.00; no sale recorded 2023-06-24: US$13499.00; no sale recorded 2023-06-24: US$13499.80; no sale recorded 2023-06-24: US$13499.10; no sale recorded 2023-06-24: US$13499.90; no sale recorded 2023-06-24: US$13499.40; no sale recorded 2023-06-24: US$13499.50; no sale recorded 2023-06-24: US$13499.30; no sale recorded 2023-08-02: US$5500.00; no sale recorded 2023-08-19: US$5499.50; no sale recorded 2023-08-19: US$5499.20; no sale recorded 2023-08-19: US$5498.50; no sale recorded 2023-08-21: US$13499.90; no sale recorded 2023-08-21: US$13499.30; no sale recorded 2023-08-21: US$13499.50; no sale recorded 2023-08-21: US$13499.00; no sale recorded 2023-08-21: US$13499.80; no sale recorded 2023-09-04: US$13151.87; no sale recorded 2023-09-27: US$13497.38; no sale recorded 2024-01-14: US$13499.40; no sale recorded 2024-01-14: US$13499.60; no sale recorded 2024-01-14: US$13499.50; no sale recorded 2024-01-14: US$6996.00; no sale recorded 2024-01-14: US$6998.00; no sale recorded 2024-01-14: US$6997.00; no sale recorded 2024-01-14: US$13499.10; no sale recorded 2024-01-18: US$7300.00; no sale recorded 2024-01-25: US$7600.00; no sale recorded 2024-02-05: US$11199.99; no sale recorded 2024-05-27: US$3500.00; no sale recorded 2024-05-31: US$6995.00; no sale recorded 2024-05-31: US$6996.00; no sale recorded 2024-05-31: US$6997.00; no sale recorded 2024-06-14: US$6997.00; no sale recorded 2024-06-14: US$6996.00; no sale recorded 2024-06-21: US$3901.00; no sale recorded 2024-06-27: US$6499.00; no sale recorded 2024-08-12: US$4228.80; no sale recorded 2024-08-12: US$4169.80; no sale recorded 2024-08-15: US$5849.10; sold recorded 2024-08-18: US$5790.61; no sale recorded 2024-09-03: US$6200.00; no sale recorded 2024-09-06: US$6233.51; no sale recorded 2024-09-30: US$6200.00; no sale recorded 2024-09-30: US$6997.00; sold recorded 2024-11-13: US$6200.00; sold recorded 2024-11-13: US$45.00; no sale recorded 2024-12-25: US$6998.00; sold recorded 2025-01-17: US$6595.74; no sale recorded 2025-01-18: US$6200.00; sold recorded 2025-01-31: US$6203.00; sold recorded 2025-02-10: US$6200.02; no sale recorded 2025-02-12: US$7350.00; no sale recorded 2025-02-12: US$6200.07; sold recorded 2025-02-14: US$6888.89; sold recorded 2025-02-20: US$21384.00; no sale recorded 2025-03-03: US$6200.50; no sale recorded 2025-03-03: US$7294.12; sold recorded 2025-03-05: US$6998.00; no sale recorded 2025-03-06: US$6199.99; no sale recorded 2025-03-10: US$4081.30; no sale recorded 2025-03-15: US$3484.00; no sale recorded 2025-03-15: US$3488.00; no sale recorded 2025-03-17: US$6998.00; no sale recorded 2025-03-19: US$6383.44; sold recorded 2025-03-19: US$11500.00; no sale recorded 2025-03-19: US$8643.00; no sale recorded 2025-03-31: US$6739.13; sold recorded 2025-03-31: US$6888.89; sold recorded 2025-04-01: US$6805.88; no sale recorded 2025-04-03: US$6200.09; no sale recorded 2025-04-10: US$6200.88; sold recorded 2025-04-14: US$3487.00; no sale recorded 2025-05-24: US$7300.76; no sale recorded 2025-06-12: US$4255.36; no sale recorded 2025-06-13: US$7000.00; no sale recorded 2025-06-19: US$7000.00; no sale recorded 2025-07-01: US$6595.74; no sale recorded 2025-07-02: US$6989.10; no sale recorded 2025-07-03: US$6200.00; no sale recorded 2025-07-08: US$8737.00; no sale recorded 2025-07-11: US$6999.00; no sale recorded 2025-07-18: US$8174.79; no sale recorded 2025-07-21: US$4291.47; no sale recorded 2025-07-21: US$7126.33; no sale recorded 2025-07-22: US$12827.39; no sale recorded 2025-07-24: US$6996.00; no sale recorded 2025-07-28: US$6999.00; no sale recorded 2025-08-01: US$6979.00; no sale recorded 2025-08-04: US$6999.00; no sale recorded 2025-08-05: US$3481.00; no sale recorded 2025-08-11: US$13327.98; no sale recorded 2025-08-12: US$7000.00; no sale recorded 2025-08-13: US$3490.00; no sale recorded 2025-08-14: US$3485.00; no sale recorded 2025-08-14: US$6862.33; no sale recorded 2025-08-14: US$8260.00; no sale recorded 2025-08-14: US$3485.00; no sale recorded 2025-08-15: US$6990.00; no sale recorded 2025-08-18: US$6208.94; no sale recorded 2025-08-18: US$6194.98; no sale recorded 2025-08-20: US$8394.00; no sale recorded 2025-08-22: US$6201.90; no sale recorded 2025-08-25: US$7021.00; no sale recorded 2025-08-28: US$6999.00; no sale recorded 2025-08-28: US$6999.00; no sale recorded 2025-09-01: US$3488.00; no sale recorded 2025-09-01: US$3487.00; no sale recorded 2025-09-09: US$6852.33; no sale recorded 2025-09-09: US$8999.85; no sale recorded 2025-09-09: US$8999.82; no sale recorded 2025-09-09: US$8999.00; no sale recorded 2025-09-10: US$4322.64; no sale recorded 2025-09-12: US$11185.00; no sale recorded 2025-09-16: US$6198.95; no sale recorded 2025-10-01: US$6199.90; no sale recorded 2025-10-05: US$3500.00; no sale recorded 2025-10-08: US$11186.00; no sale recorded 2025-10-09: US$6200.99; no sale recorded 2025-10-13: US$6326.53; no sale recorded 2025-10-22: US$5779.54; no sale recorded 2025-10-22: US$6190.00; no sale recorded 2025-10-27: US$6204.49; no sale recorded 2025-10-29: US$5571.91; no sale recorded 2025-11-01: US$7541.29; no sale recorded 2025-11-04: US$6007.39; no sale recorded 2025-11-06: US$6190.00; no sale recorded 2025-11-12: US$6212.68; no sale recorded 2025-11-12: US$5293.31; no sale recorded 2025-11-12: US$6250.00; no sale recorded 2025-11-12: US$6190.00; no sale recorded 2025-11-13: US$6200.02; no sale recorded 2025-11-17: US$8242.30; no sale recorded 2025-11-17: US$7569.77; no sale recorded 2025-11-19: US$9696.95; no sale recorded 2025-11-24: US$6200.99; no sale recorded 2025-11-25: US$6215.00; no sale recorded 2025-11-26: US$6200.96; no sale recorded 2025-11-27: US$6180.00; no sale recorded 2025-11-27: US$6180.00; no sale recorded 2025-11-28: US$8537.40; no sale recorded 2025-12-02: US$6200.10; no sale recorded 2025-12-03: US$6200.10; no sale recorded 2025-12-08: US$6200.10; no sale recorded 2025-12-08: US$6200.02; no sale recorded 2025-12-10: US$6199.90; no sale recorded 2025-12-12: US$6195.00; no sale recorded 2025-12-15: US$6190.00; no sale recorded 2025-12-17: US$6486.50; no sale recorded 2025-12-17: US$6195.00; no sale recorded 2025-12-18: US$6190.00; no sale recorded 2025-12-22: US$6966.29; no sale recorded 2025-12-24: US$6179.09; no sale recorded 2025-12-29: US$7908.87; no sale recorded 2025-12-30: US$6998.95; no sale recorded 2025-12-30: US$6999.00; no sale recorded 2026-01-06: US$6299.00; no sale recorded 2026-01-06: US$6195.00; no sale recorded 2026-01-14: US$6391.75; no sale recorded 2026-01-19: US$6235.00; no sale recorded 2026-01-20: US$6199.34; no sale recorded 2026-01-29: US$6666.67; no sale recorded 2026-02-27: US$6411.84; no sale recorded 2026-03-03: US$6407.75; no sale recorded 2026-03-10: US$7000.00; no sale recorded 2026-03-11: US$6819.89; no sale recorded 2026-03-12: US$8318.10; no sale recorded 2026-03-13: US$6294.00; no sale recorded 2026-03-13: US$6295.00; no sale recorded 2026-03-14: US$6995.00; no sale recorded 2026-03-17: US$6375.24; no sale recorded 2026-03-17: US$6399.75; no sale recorded 2026-03-22: US$4726.00; no sale recorded 2026-04-09: US$7000.00; no sale recorded 2026-04-10: US$6995.99; no sale recorded 2026-04-17: US$7519.71; no sale recorded 2026-04-22: US$7101.94; no sale recorded 2026-05-04: US$6412.75; no sale recorded 2026-05-05: US$6377.76; no sale recorded 2026-05-08: US$6390.95; no sale recorded 2026-05-21: US$6381.75; no sale recorded 2026-05-25: US$6376.87; no sale recorded 2026-05-27: US$6402.85; no sale recorded 2026-05-27: US$6419.25; no sale recorded 2026-05-28: US$6441.31; no sale recorded 2026-06-01: US$6441.36; no sale recorded 2026-06-02: US$7143.68; no sale recorded 2026-06-04: US$6113.00; no sale recorded 2026-06-04: US$6483.21; no sale recorded 2026-06-05: US$6113.00; no sale recorded 2026-06-05: US$6599.00; no sale recorded 2026-06-05: US$7694.48; no sale recorded 2026-06-05: US$6462.76; no sale recorded 2026-06-05: US$6441.36; no sale recorded 2026-06-10: US$6868.41; no sale recorded 2026-06-11: US$6459.30; no sale recorded 2026-06-18: US$6456.09; no sale recorded 2026-06-18: US$6446.31; no sale recorded 2026-06-20: US$8155.20; no sale recorded 2026-06-24: US$6461.31; no sale recorded 2026-06-25: US$6451.31; no sale recorded 2026-07-07: US$7501.32; no sale recorded 2026-07-09: US$8150.40; no sale recorded 2026-07-10: US$7353.42; no sale recorded 2026-07-13: US$6796.00; no sale recorded 2026-07-13: US$6798.00; no sale recorded 2026-07-14: US$8089.62; no sale recorded 2026-07-15: US$6995.75; no sale recorded 2026-07-15: US$6985.53; no sale recorded 2026-07-21: US$6986.74; no sale recorded 2026-07-31: US$6986.74; no sale recorded 2026-08-04: US$5124.90; no sale recorded 2026-08-05: US$6970.84; no sale recorded 2026-08-10: US$6971.70; no sale recorded 2026-08-11: US$6970.76; no sale recorded 2026-08-31: US$7003.25; no sale recorded 2026-09-03: US$7005.15; no sale recorded 2026-09-09: US$6970.75; no sale recorded 2026-09-14: US$7511.56; no sale recorded 2026-09-21: US$6991.30; no sale recorded 2026-09-21: US$6970.75; no sale recorded 2026-09-23: US$995.71; no sale recorded 2026-10-07: US$6970.85; no sale recorded 2026-10-19: US$7007.40; no sale recorded 2026-10-23: US$6967.76; no sale recorded Sold recorded No sale recorded Monthly median
Logarithmic price scale (price + 1). Dates are listing starts.
Median recorded price, all years $6852.33 235 plotted records from 235 US-dollar records in this range. Monthly medians use all records in each calendar month.