Missing "SSTable Count" metric when using nodetool with "--format" option

{  "total_number_of_tables": 38,  "stress_test": {    "write_latency_ms": 0.8536725334338424,    "tables": {      "res1": {        "average_tombstones_per_slice_last_five_minutes": null,        "bloom_filter_off_heap_memory_used": "159256",        "memtable_switch_count": 754,        "maximum_tombstones_per_slice_last_five_minutes": 0,        "memtable_cell_count": 0,        "memtable_data_size": "0",        "average_live_cells_per_slice_last_five_minutes": null,        "local_read_latency_ms": "NaN",        "local_write_latency_ms": "NaN",        "pending_flushes": 0,        "compacted_partition_minimum_bytes": 785940,        "local_read_count": 0,        "sstable_compression_ratio": 0.6294161376582798,        "dropped_mutations": "52751",        "bloom_filter_false_positives": 0,        "off_heap_memory_used_total": "58842196",        "memtable_off_heap_memory_used": "0",        "index_summary_off_heap_memory_used": "18972",        "bloom_filter_space_used": "159408",        "sstables_in_each_level": [],        "compacted_partition_maximum_bytes": 4055269,        "space_used_total": "302694398635",        "local_write_count": 297111,        "compression_metadata_off_heap_memory_used": "58663968",        "number_of_partitions_estimate": 99614,        "maximum_live_cells_per_slice_last_five_minutes": 0,        "space_used_live": "302694398635",        "compacted_partition_mean_bytes": 3827283,        "bloom_filter_false_ratio": "0.00000",        "percent_repaired": 0,        "space_used_by_snapshots_total": "0"      }    },    "read_latency_ms": null,    "pending_flushes": 0,    "write_count": 594308,    "read_latency": null,    "read_count": 0  }}
 

----------------
Keyspace : stress_test
        Read Count: 0
        Read Latency: NaN ms
        Write Count: 594308
        Write Latency: 0.8536725334338424 ms
        Pending Flushes: 0
                Table: res1
                SSTable count: 19                
                Space used (live): 302694398635
                Space used (total): 302694398635
                Space used by snapshots (total): 0
                Off heap memory used (total): 58842196
                SSTable Compression Ratio: 0.6294161376582798
                Number of partitions (estimate): 99614
                Memtable cell count: 0
                Memtable data size: 0
                Memtable off heap memory used: 0
                Memtable switch count: 754
                Local read count: 0
                Local read latency: NaN ms
                Local write count: 297111
                Local write latency: NaN ms
                Pending flushes: 0
                Percent repaired: 0.0
                Bloom filter false positives: 0
                Bloom filter false ratio: 0.00000
                Bloom filter space used: 159408
                Bloom filter off heap memory used: 159256
                Index summary off heap memory used: 18972
                Compression metadata off heap memory used: 58663968
                Compacted partition minimum bytes: 785940
                Compacted partition maximum bytes: 4055269
                Compacted partition mean bytes: 3827283
                Average live cells per slice (last five minutes): NaN
                Maximum live cells per slice (last five minutes): 0
                Average tombstones per slice (last five minutes): NaN
                Maximum tombstones per slice (last five minutes): 0
                Dropped Mutations: 52751*  
----------------